In this blog post, we explore the captivating research of quantum dots with Professor Armando Rastelli. Discover his career journey, favorite experiments, and the fascinating applications of quantum dots in secure communication and beyond. Armando’s insights offer a unique glimpse into the life of a modern scientist.
About the Guest:
Armando Rastelli
Professor Armando Rastelli is a renowned scientist in the field of semiconductor physics, currently based at Johannes Kepler University Linz in Austria. With an impressive background in studying the optical properties of quantum dots, Armando’s research has significant implications for the future of secure communication and quantum technologies. His journey includes international experiences and a deep passion for uncovering the mysteries of these tiny particles.
![](https://thesciencetalk.com/wp-content/uploads/2024/04/1_Armando_Rastelli_Linz_Austria-2-scaled.jpg)
Professor Armando Rastelli is a renowned scientist in the field of semiconductor physics, currently based at Johannes Kepler University Linz in Austria. With an impressive background in studying the optical properties of quantum dots, Armando’s research has significant implications for the future of secure communication and quantum technologies. His journey includes international experiences and a deep passion for uncovering the mysteries of these tiny particles.
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5 Key Takeaways from this Episode of Under the Microscope:
- Understanding Quantum Dots: Quantum dots are tiny semiconductor particles with unique optical properties dependent on their size, used in applications from TV screens to secure communication.
- Research Applications: Armando’s team creates quantum dots and studies their properties to explore potential technological applications, such as optoelectronic devices and single-photon sources for secure communication.
- Career Journey: Armando’s path to becoming a professor involved various international experiences, from working in an underground lab in Italy to research positions in Switzerland, Finland, and Germany.
- Beyond the Lab: Life as a scientist includes exciting experiments but also involves waiting for rare particles and overcoming potential frustration in research.
- Future of Quantum Dots: The future applications of quantum dots could revolutionize secure communication by using single photons to create and distribute secure encryption keys.
In this episode, we cover:
Armando’s Research:
Dive into the world of quantum dots, tiny semiconductor particles that have unique optical and electronic properties. Armando explains how these properties change with the size of the quantum dots, making them useful for a range of applications. Learn about the cutting-edge techniques his team uses to create and study these fascinating structures.
Armando’s Career Journey:
From his early days disassembling gadgets to his current role as a professor, Armando’s journey is filled with diverse experiences. He has worked in underground labs in Italy, held research positions in Switzerland, Finland, and Germany, and now leads a team at Johannes Kepler University Linz. His story is one of passion, persistence, and international collaboration.
Armando’s Favorite Research Experiment:
Among the many experiments Armando has conducted, his favorite involves exploring the optical properties of quantum dots. This experiment not only deepened his understanding of these particles but also opened up new possibilities for their application in technologies such as single-photon sources, which are crucial for secure communication.
Life as a Scientist – Beyond the Lab:
Armando shares insights into the daily life of a scientist, which goes beyond just conducting experiments. It includes international collaborations, teaching, mentoring students, and overcoming the inevitable challenges and frustrations that come with research. Armando emphasizes the importance of patience and resilience in the scientific field.
Armando’s 3 Wishes:
In a light-hearted segment, Armando reveals his three wishes for the future of his research and the scientific community. These include advancing the understanding of quantum dots, fostering more international collaborations, and inspiring the next generation of scientists.
Armando’s Time on RealSci_Nano:
Armando reflects on his experiences with the RealSci_Nano project, highlighting its role in bridging the gap between complex scientific concepts and public understanding. He discusses how the project has helped him communicate his research to a broader audience and the impact it has had on his career.
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Transcript
Pranoti Kshirsagar: 12 months 12 labs one source to unite them all. Hi everyone, my name is Pranoti I’m your host of Under the Microscope. I’m very excited to introduce you to today’s guest, Armando Rastelli, professor at the Institute of Semiconductor and Solid State Physics at the Johannes Kepler University Linz in Austria.
Pranoti Kshirsagar: welcome Armando, lovely to have you on Under the Microscope. How far is Linz from Vienna, because I think most people know Vienna.
Armando Rastelli: Yeah, it’s about 200 kilometers.
Pranoti Kshirsagar: Okay.
Speaker 3: There is a very good train connection.
Exploring Quantum Dots
Speaker 2: Armando, please tell me about your research. What exactly are you doing in Linz, which is 200 kilometers from Vienna?
Speaker 2: Please explain what exactly are you doing?
Speaker 3: Yes, we are working with these tiny objects, which are quantum dots. And just to understand, so you can imagine this as a quantum dot, or maybe you can take it as a chocolate chip in a muffin.
Speaker 3: if it would [00:01:00] be as big as a chocolate chip in a muffin, then the muffin would have a diameter of about five kilometers. So very small, and they are made of special materials, which are semiconductors. These are the materials which are inside your mobile, your TV, your computer, and so on.
Speaker 3: And what we are doing is that we make these quantum dots. And then we study their properties and we try to see if they are good for some special applications.
Speaker 2: While you’re telling me this, I’m imagining a cookie and I’m drawing it out.
Speaker 2: Okay. Five kilometer. Let’s go with that, right? Five kilometer. That’s a really big chocolate chip cookie. I would love, okay, focus.
Understanding Quantum Dot Properties
Speaker 2: And the quantum dot is like a, so that is to understand the scale, right?
Speaker 2: The dimensions at which we are, which at which we are working on. So how big are these quantum dots? Like what, how big, like in reality?
Speaker 3: Typical size is about 50 nanometers.
Speaker 2: So that’s basically five. [00:02:00] multiplied by 10 to the power minus 10. So like angstrom, if that’s what, the listeners, understand.
Speaker 2: So five angstrom.
Speaker 3: It’s a 500 angstrom.
Speaker 2: 500 angstrom. Wow.
Pranoti Kshirsagar: What are the shapes of these quantum dots? Are they always like the table tennis ball that you showed me
Armando Rastelli: Actually, the dots we are dealing with are like squeezed balls, so maybe a flat object. You can imagine like a lens or, as I say, the chocolate chip, maybe. a diameter of about 50 nanometers and the height of 7 nanometers. So a ratio between, width to height of about 10.
Speaker 2: Ah, okay.
Speaker 2: Okay. So it’s not like a sphere. It’s more yeah, it’s more like a
Speaker 3: small bun or something like an object like this
Speaker 2: Or if you just take like a sphere and you cut it like somewhere in the half
Speaker: It’s
Speaker 2: Okay. Okay. So you make these quantum, you and your group, of course, you make these quantum dots. And what do you do [00:03:00] with it?
Applications of Quantum Dots
Speaker 2: Okay, you made the quantum dots, which are not, Chocolate chip chips in the chocolate, but why do you do this? Why? Why? Why do we need this?
Speaker 3: first of all, we have special ovens to cook these quantum dots. it’s not muffins. Why we do that? Because, the behavior of these structures, it’s very special. Just to illustrate it, so that the optical properties of these quantum dots depend on size.
Speaker 3: if you take a quantum dot, which is small, its color tends to go towards the blue, while a big quantum dot has a color which tends to go to the red. That’s what happens when sizes get small. there are many special properties of these quantum dots, which can be described by quantum mechanics.
Speaker 3: We want to understand better these properties and to take profit of them, maybe for some technological application.
Speaker 2: Okay, so if we take, let’s say, a cookie, depending on where we cut it, that will define how big the size is. That’s not how it is made, of course, but just for visualization purposes.
Speaker 2: And then [00:04:00] the smaller it is, the bluer
Speaker 3: Yeah, I made the example with color, but now if you are sticking to the example of a cookie It’s like when you start slicing, the taste changes, and maybe you can decide the size where it tastes the better.
Speaker 2: Oh, that is cool. That I like.
Speaker 3: Or maybe you start cutting your piece of chocolate at the beginning, it’s not very sweet.
Speaker 3: and then you stop cutting and then you say, okay, this is the right size.
Speaker 2: this is what I want. This is my application.
Speaker 3: exactly.
Speaker 2: So when you say size, what dimensions are we talking?
Speaker 3: Yeah. That depends also on the materials we are considering.
Speaker 3: So if, for our quantum dots, we could go from sizes, which are just one nanometer tall, up to maybe 15, 20 nanometers. At some point, if the size is too big, we lose the cool properties of these quantum dots that are not so quantum anymore.
Speaker 3: And so there is a certain range, which is [00:05:00] of the order of a few nanometers up to a few tenths of nanometers.
Speaker 2: So the magic happens in the nano range and the bigger it gets, the more it’s yeah, whatever.
Speaker 3: We understand everything.
Speaker 2: The basic stuff, which everyone knows, but there’s no fun in that, of course, when you say the size of the quantum dot, when you say like 10, 10 nanometer, two nanometers, which is the height of this bump, so to say, so is it always that everyone is reporting the height? So when someone says we created quantum dots, which are, I don’t know, 30 nanometer or so, it’s always the height, right?
Speaker 2: Not the spread.
Speaker 3: I should be precise that there are actually two major classes of quantum dots and the quantum dots one here’s the most actually there are colloidal quantum dots and they’re almost spherical. So these are the quantum dots which are already they were awarded or the discoverers of these quantum dots were awarded [00:06:00] the Nobel Prize.
Speaker 3: just last year.
Speaker 2: Your quantum dots are the ones that are these bumps.
Speaker 3: The technical word is, so for the first ones, the round ones, they are called colloidal quantum dots, and they find already applications, for instance, in, brilliant TV screens. And our quantum dots are called epitaxial quantum dots.
Speaker 3: they are more, suitable for optoelectronic devices and they are flat usually or
Speaker 2: Flattish, like bumpy. Okay.
Speaker 3: Yeah.
Speaker 2: Epitaxial quantum dots. Okay. Epitaxial quantum dots, which are.
Speaker 3: The colloidal.
Speaker 2: colloidal ones. Okay. And the colloidal ones are like the LCD screen or whatever the screens to make the screens better or more clear.
Speaker 2: And the epitaxial quantum dots. are for optoelectronic properties.
Speaker 3: So for instance, they are interesting for lasers.
Speaker 2: For
Speaker 3: noble sources of quantum light, like what we have for the contour project.
Speaker 2: For the contour project with the lasers or for the single photon emission and stuff. With the colloidal quantum dots, you already [00:07:00] gave an example that like with our TV screens and that is their application.
Speaker 2: But about the epitaxial quantum dots, can you give me a real life example of where we might already have it or we can have it if we don’t have it already?
Speaker 3: These are applications which are still classical. they belong to the first quantum revolution where quantum mechanics made a difference, the first time.
Speaker 3: all what we have, like the chips or the LEDs lasers, belong to the inventions or discoveries which belong to the, First quantum revolution. now these quantum dots, if these actual quantum dots could make a difference also for the second quantum revolution. But we want to use the more delicator and more fragile properties of quantum mechanical systems.
Quantum Dots in Secure Communication
Speaker 3: And one particular application is in secure communication, where you want to encrypt your messages in an absolutely secure way. one of the approaches is to try [00:08:00] to create secure keys. Using properties of single photons, and that’s what we try to do many other groups in the world have sources of single photons or entangled photons.
Speaker 3: Use these photons to create and distribute secure keys with which you can encrypt messages.
Speaker 2: Now it is starting to form a story in my mind as well, because what Doris, spoke about, what Toby spoke about as well with the secure communication and for the listeners or the watchers.
Speaker 2: if you are following the contour. edu Instagram, you would. Get the jokes now why there is the security jacket person who is going around with the suitcase. You will understand that. So for the contour project, right? The source that at the moment with you, that one has circular rings.
Speaker 2: It has circular rings. So now help me understand this. So your quantum dots, [00:09:00] which are epitaxial, which are these bumps, how do they combine?
Speaker 3: Yeah, that’s a very good question. So essentially you have a quantum dot and this is a, for instance, if you are using it as a source of light, you have to imagine that this light is emitted by the quantum dot.
Speaker 3: But usually if you don’t do anything, the quantum dot emits light. in all directions.
Speaker 2: Right.
Speaker 3: And imagine you want to collect light either with your eyes or actually in practice through an optical fiber. So you want to have light to be directed in a specific direction.
Speaker: Right.
Speaker 3: And those are the ones you are referring to are exactly for this purpose.
Speaker 3: To make sure that light, which should be lost in this direction, for instance, is redirected towards your direction. So that’s the idea. Actually, there is a mirror behind the quantum dot so that all light, which is coming towards me is also redirected in your direction.
Speaker 3: And also these rings make sure that all the light or maybe 90 percent of the light, which is emitted. comes to your direction. And these rings are much [00:10:00] bigger, than the quantum dot itself. so the quantum dot could be maybe 14 nanometers big. And the disk where it is embedded is about 10 times bigger.
Speaker 3: And then these rings one order of magnitude larger. So we are talking about a structure which has a footprint of a few, micrometers, 100 times bigger than the quantum dot itself. The source is very tiny. And around there is a big thing. But this is similar to what we have for LEDs, for instance, light emitting diodes.
Speaker 3: If you look at the chip inside the LED, it’s very small. And to make sure that light comes towards you, there is a lens in front. So these rings are a kind of very specialized lens with very high efficiency, because we want to collect single photons. And we want to have all of them. You cannot afford any loss.
Speaker 3: For an LED, you are happy with a simple lens, for a single photon source, you want to have a very special lens, which makes sure that you get all light where you want.
Speaker 2: Oh, that is so cool. I think I’m going to be a pro after interviewing [00:11:00] all of you contour heroes.
Speaker: I’m sure
Speaker 2: at the end of it, I would be like, okay, just ask me anything.
Speaker 2: I know everything. Collider, quantum dots, epitaxial quantum dots, secure communication. Why are the rings? What’s with the bumps and everything? Oh, I’m going to be a pro.
Speaker 3: And then we send the students to you to do that because you are collecting the information from all the groups, many groups in Europe.
Speaker 2: Exactly. 12 months, 12 labs, one source to unite them all.
Speaker 3: Yeah.
Speaker 2: Thank you, Armando.
Speaker 3: I support you.
Speaker 2: Thank you. I’m going to, okay, on record now, Tobi and Doris, I know you’re going to watch this and you’re going to listen to this episode.
Speaker 2: I have Armando on record, one source to unite them. Yes.
Speaker 3: Or maybe we could say that at the end you will get entangled with all of us.
Speaker 2: So we’ll
Speaker 3: We will distribute entanglement for you. Okay,
Speaker 2: don’t
Speaker 3: take me too serious.
Speaker 2: I love that.
Speaker 3: Entanglement is something fragile,
Speaker 2: Yeah true.
Speaker 2: We can do so many things here, but we will have fun with it, for [00:12:00] sure. this is great. This is really cool. Armando, tell me, I’m always curious. how did this happen? was a five year old or a 10 year old Armando thinking that, yeah, I’m going to be a professor in Linz in Austria.
Armando’s Career Journey
Speaker 2: How did you end up becoming a professor at, the University in Linz leading a group, being a professor? How did that happen? Tell me about your career journey.
Speaker 3: Okay, since you mentioned the young age,
Armando Rastelli: I liked very much playing and dismounting all the technological equipment I had at home.
Armando Rastelli: I thought I would become,
Armando Rastelli: an electrical technician. Then at some point, at the age of maybe 16, I discovered something like physics. I said, Oh, this is really cool. And I want to do that. So I studied physics.
Speaker 3: I made my, thesis work. My, master’s thesis. It was called Lauria in Italian.
Speaker 3: underground lab, which is a tunnel under a mountain. So it’s about 1. 5 kilometers below the top of the [00:13:00] mountain. We would collect high energy particles coming from the space, muons and neutrinos and stuff like that. So I was working there and it sounds very fascinating, but in practice for a physicist, There’s not much to do, or you don’t have so much freedom to try out things which come to your mind because the experiments are very big.
Speaker 3: So
Armando Rastelli: then I switched during my PhD to solid state physics and semiconductor physics,
Speaker 3: and then
Armando Rastelli: got my PhD in Italy and working also at the ETH Zurich in Switzerland. Then I was also in Finland for some time, for three months. And then I moved to Stuttgart, to Germany. And my career path went to Dresden, to Germany, until 2012.
Armando Rastelli: And then 2012, I got a professorship here in Linz. where I could build up my own group and,
Armando Rastelli: I’m here.
Speaker 2: Okay.
Speaker 3: It’s a random world.
Speaker 2: Yeah. Quite an unusual path. I still have so many [00:14:00] questions about the master thesis in the tunnel. So you mentioned there were the materials from space during your master time.
Speaker 3: High energy particles.
Speaker 2: energy particles.
Speaker 2: Yeah.
Speaker 3: It’s a cosmic rays.
Speaker 2: Okay. These are not UFOs that you’re talking about.
Speaker 3: no. It’s just very tiny point like particles, even smaller than atoms.
Speaker 2: so what do you do? You go into the mountain and the tunnel and you just grab some sand or some soil.
Speaker 3: No . No, they’re coming. So you have very specialized detectors, with very big area. So you need, many square meters of detectors or, tents or hundreds or square meters of detectors or cubic meters or thousands of cic meters of detectors. . And then you wait, you just wait until the, some particle comes from space and it has enough energy to cross the full mountain.
Speaker 3: or it has weak interaction with rock. And then you collect these particles and look at their properties, look at their energy, their [00:15:00] direction, and so
Speaker 2: Okay, now I understand what you mean when you say that it sounds super fancy, but in reality that It’s
Speaker 3: just a matter of weighting and discriminating this particle for something or looking what is interesting.
Speaker 3: So many things are just known and, the exotic things which are not known are very rare.
Speaker: huh.
Speaker 3: may take you decades. And there’s a very high potential for frustration at some point.
Speaker 2: Sometimes you don’t find anything for decades and sometimes you find something.
Speaker 2: You started in Italy, then you went to Zurich. So in Switzerland, then you went to Finland.
Speaker 3: Yes. To the Tampere.
Speaker 2: the Tampere in Finland. Then you went to Stuttgart in Germany. Were you at the Max Plank in Stuttgart?
Speaker 3: Yes. Really? Yes. Max Plan Institute. let’s go portion.
Speaker 2: So you were at the MAX plan in Stuttgart? That’s where I did my masters. I was there for three years. Between 12 to 15? Yes.
Speaker 3: Okay. I was already gone.
Speaker 2: [00:16:00] Were you also in Faki department ing?
Speaker 3: yes.
Speaker 2: No way.
Speaker 3: It was a subgroup, of,
Speaker 2: which one were you?
Speaker 3: Ah, no, it was already gone when you came because it was, Oliver Schmidt, he was, my boss, was, a B Taxi group, so it was shut down.
Speaker 2: I joined, I came in 2012, end of 2012. I think by then you already had moved on.
Speaker 3: I had left in 2007.
Speaker 3: So five years. Okay,
Speaker 2: but we have that connection then with South Easting.
Speaker 3: Many people make a stop at Max Planck Institute.
Speaker 2: Yeah, very,
Speaker 3: yeah,
Speaker 2: So then after Stuttgart, you were in Dresden. In Germany.
Speaker 3: Yeah.
Speaker 2: Which institute? ’cause there are like 50,
Speaker 3: it was the LA IIFW.
Speaker 2: Ah, okay.
Speaker 2: Because they have IFW and IPF as well. I think the polymer one. Yeah. that is cool. You are now closer to [00:17:00] Italy. That is quite a, you are a definition of traveling scientist. I’m sure you have had a lot of research projects which are very interesting. So now this question is the one which I get the most, hate for.
Speaker 2: So please don’t hate me, Armando.
Research Highlights and Techniques
Speaker 2: If I ask you to pick one research project that you’re most proud of, or the most fun and quirky one, can you pick one research project from your journey as a scientist, and explain it to us in simple words in the section we call In Other Words?
Speaker 3: So after my master’s thesis, I started working with quantum dots, and on different aspects of these quantum dots, conventional way of making quantum dots relies on stress. So essentially what you do is you start with a substrate material. you have to imagine a crystal with a perfectly arranged set of atoms. forming a lattice. you can imagine that like the squares of this piece of paper.
Speaker 3: And what you do is [00:18:00] that you put on this substrate another material, which would form also a crystal. And maybe the spacing between the lattice planes It’s different, and the usual way is to take a material which is slightly larger. So what happens is that when you start depositing this material, the first layers try to adapt their distance, their interatomic distance, to the underlying substrate.
Speaker 3: But to do there is elastic energy, or stress, piling up in this layer. And what the layer does to try to relax, because as we humans, we don’t like to be stressed. the same thing happens for this material. So after a certain layer, which is stressed, you have islands forming on this material, bumps where the atoms try to get far away from the substrate, which tries to tell them how to arrange.
Speaker 3: So these atoms build up bumps. And these bumps allow the atoms to get farther away and get to their natural [00:19:00] distance. Okay.
Exploring Stress-Free Quantum Dots
Speaker 3: Then these bumps are covered with the same material as the substrate. Usually these bumps, you have to imagine these bumps. We were discussing about these, portions of a sphere.
Speaker 3: They are covered with the same material as the substrate, but they still stress. Okay. And, this stress has some drawbacks. when I started my postdoc, I was wondering if we could get dots without stress. But the question is not trivial, because you need stress to create these dots, and these dots stay stressed.
Speaker 3: Okay, so in the first place, you need to find a way to make dots without stress. So without the driving force for making the dots. That’s the question.
The Breakthrough Moment
Speaker 3: This was the first thing I tried to do during my postdoc time in Stuttgart. So it was a very long day. I started at maybe nine in the morning and I kept doing, I had this idea.
Speaker 3: I wanted to see if this works. And then I have grown the sample. I produce the samples and take them out from this [00:20:00] oven, which is there. molecular beam epitaxy and then put them under the microscope and then looked at them at six in the morning of the day afterwards. I found the proof that they had created a new kind of golden dots and it was really exciting.
Speaker 3: So nobody was there, around, but I called home my parents at six in the morning to Italy and say, Oh, I found something cool. I really liked it.
Challenges and Skepticism
Speaker 3: Then, it was a bit disappointing to see that nobody was caring much about that because It was exotic, and whenever you do something new, people are skeptical, maybe it’s something useless, and so on.
Speaker 3: it took many years, but people started getting interested, and people started having new ideas on how to make these holes, and how to fill them, and then we picked up those ideas, we continued developing them, and then it’s very nice to see that after 20 years, now these quantum dots, which are without stress, are taking over the field.
Speaker 3: Because they have much better properties.
Speaker 2: This is so cool.
Understanding Quantum Dots
Speaker 2: [00:21:00] So you basically talking about the science aspect of it, you basically did like a negative correction. That is how the quantum dots are happening with the stress. So what you do is instead of having a flat surface, you do like a.
Speaker 2: You make holes, so to say, when it will be stressed, then it will just rise up and it won’t be a bump then it will just be instead of having a hole of let’s say 10 nanometer deep, it would be a 8 nanometer deep, something like that.
Speaker 3: It’s not much about matter of height. The question is the materials which I can combine.
Speaker 3: So in this, in the stress quantum knots, you need to combine materials which are different lattice constant.
Speaker 3: Actually, you don’t, it’s better to use material which has the same LA concept as the substrate material. and then this will be unstressed.
Speaker 2: It’s mainly, you are controlling or you are creating the quantum dots, which are. Not stressed, like relaxed quantum dots. [00:22:00] It’s not about the final product, when we are doing this bump, Lord bump thingy crest or the trough, sort of a thing.
Speaker 2: It’s more about when the materials are coming in contact to create these quantum dots that is the key. Oh, that is so cool. Now I understand it even better.
Armando Rastelli: well, you have the same lattice, constants. So you can combine two materials, which have the same size, the atoms are at the same distances and still have an object, a three dimensional object. which behaves as a quantum dot.
Speaker 2: Armando, this is so cool! Thank you.
Speaker 3: I’m happy that you like it.
Speaker 2: It’s amazing.
Personal Research Stories
Speaker 2: And I can totally imagine this coming back to the emotional aspect of it, that you started working like on a normal time, let’s say 9am or something.
Speaker 2: And then next day 6am is [00:23:00] when you, I got the result, like the first proof of, oh, I made it in the molecular beam epitaxy and then probably under the microscope, under the microscope, this is. This is so cool, and this reminds me also of the first time, so when I was doing my master thesis at the, say, Max Planck in Stuttgart, probably we were in two different buildings and two different, of course, at two different times.
Speaker 2: My master thesis was about growing graphene, twisted bilayer graphene. With chemical vapor deposition and it was in the clean room. The oven was in the clean room and, the process usually was taking 24 hours or 48 hours for the growth. Cause you are slowly growing it. And I was in the lab at six 30 or seven in the morning.
Speaker 2: So to turn off the oven and to take the sample out and stuff. And there was no one else in the lab. Also, it was safe because there was no chemical reaction happening anymore. And it [00:24:00] was the first time that I saw with all that clean room suit and everything. I had the sample, which was like at 45 degree angle.
Speaker 2: it was a copper, copper, piece of copper, and it had these. Hexagons, which were bright on it. And that was the first time I created graphene, which you could see with your naked eyes. And of course I had to put it under the microscope, electron microscope, do Raman to confirm it is monolayer and everything.
Speaker 2: But that was the first time and there was no one around. And I was like, Oh my God. So I really had to go out of the lab, go to tiny lake that we have at the Max Planck campus in Stuttgart and just breathe, behind the building, there is the, this tiny, not a lake, it’s a pond, almost some water body.
Speaker 2: And that’s where I had to go and be like, there was the bench and I was like, finally it happened. So I totally understand That you called your parents like, Hey, I got it. I got it. What I wanted. Your parents [00:25:00] probably didn’t know
Speaker 3: what to do.
Speaker 2: wasn’t a piece
Speaker: of
Speaker 2: That is so cool. And this was something that you did, let’s say, what, 14 years ago,
Speaker: 20 years ago.
Speaker 2: Okay. This was before the graphene paper came out. That was in 2004.
Speaker 3: Yes.
Graphene Discoveries
Speaker 3: Oh, about graphene. So tell me,
Speaker 2: tell me graphene story.
Speaker 3: During my PhD I was doing STM, so I was scanning, telling microscopy, to calibrate the scanner, we had a, I had a piece of a, para, HO hg ,
Speaker: yes.
Speaker 3: And actually the standard way of calibrating STM was to look at the surface of graphite and actually to get it clean, we had a piece of scotch and peeling off graphite.
Speaker 3: And I remember the moment where I did it the first time and looking at what I peeled off. Oh, this looks really cool. I can peel off. Layers of this stuff. Okay, but let’s calibrate the scanner. So throw away these things.
Speaker 2: You threw away graphene, Armando.
Speaker 3: [00:26:00] I remember that I was curious about that.
Speaker 3: But I was under pressure because I had to obtain results on my relatively boring compared to graphene. Yeah, this was already standard. So it was the discovery of the scotch was okay. But the only, the new thing was to look at what you feel of. Exactly.
Speaker 2: I think this is a standard practice, right? You take a piece of graphite and then you exfoliate the top layer off so that it’s like, You got a clean surface for calibration
Speaker: I missed the Nobel prize.
Speaker 2: Yeah you’re working on cooler stuff now so it’s fine but this is really cool so you made graffiti before. Without even realizing it. And just like you, many other probably made graphene without realizing it. So cool. Awesome. So this was your research project that you’re super proud of, but of course we are not playing favorites here or anything like that.
Speaker 3: I must also say that many others, of course, contributed to the field and that the discovery is just on the way. So [00:27:00] there are many ideas and many coincidences Which must come together at the right time, right? Absolutely.
The Joy of Being a Scientist
Speaker 2: Armando, it’s very clear to me that the research aspect of being a scientist, being a professor, is really what drives you.
Speaker 2: what else do you like about being a scientist?
Speaker 3: I think, one of the aspects I like is the fact that if you’re a scientist, you’re allowed to stay child, all life. Absolutely. And to keep playing. The difference is that you get more and more expensive toys to play with.
Speaker 3: what I like is also to transmit my passion and my knowledge to students through teaching and also through supervision. And those are the things I like the most. And we have also quite much freedom, flexible working times usually. And that’s nice.
Speaker 3: And also, a very important aspect is that we get in touch with the international community. So we have colleagues everywhere in the world. So if you go to some place, there is a very good chance that you know people there, maybe the US or India or China [00:28:00] or Brazil. And, you get to know many people, many cultures.
Speaker 2: yeah, definitely. And that’s why I think Doris also, she also mentioned this. She had this. Science Bridges culture sticker, which she had on like the pin on now. Absolutely. And I completely agree with the expensive toys. The toys just get more and more expensive and more and more fun to play with.
Speaker 2: It’s so much fun to, ah, it is so cool. And this is. Important, right? Also the collaboration and international community. And the two examples of that are right behind you. If anyone is watching, there is the contour project, which is the, a quantum emitters journey through Europe. And then there is the quant a quanta, which is quantum science, Austria.
Speaker 2: Tell me a bit about Quanta and then tell me a bit more about Quantour.
Speaker 3: Yeah. Okay. Maybe I can start with, Quantae.
Quanta: Austria’s Quantum Science Hub
Speaker 3: Quantum Science Austria is a new, cluster of excellence, in Austria. So it’s funded by the FWF,
Armando Rastelli: the [00:29:00] Austrian Science Funds. The mission of this project is to
Armando Rastelli: bring together all the scientific community working on quantum science and on different aspects of quantum science in Austria together.
Armando Rastelli: The coordination is the University of Innsbruck, and we as the Johannes Kepler University of Linz are part of this initiative. Then there is the Technical University of Vienna, the University of Vienna, the Academy of Sciences, and the IST Austria. So we have many people, about
Speaker 3: 60 PIs.
Armando Rastelli: scientists and their own groups.
Armando Rastelli: So it’s a very big community,
Armando Rastelli: working all together to push forward the frontiers
Speaker 3: of
Armando Rastelli: quantum science.
Speaker 3: Austria, right? All of these 60
Speaker 2: PIs or groups are in Austria. That is amazing.
Speaker 2: Yeah.
Speaker 3: So actually, it’s slightly different from the initiatives in Europe. So our focus is on fundamental science rather than technology.
Speaker 3: Because, there is no technological development without fundamental science. And we [00:30:00] want to make sure that fundamental science. keeps this momentum.
Speaker 2: Yeah, you’re absolutely right. I’ve only heard of these clusters of excellence. This is mo mainly in the tech transfer or spinoff sort of a space.
Speaker 2: but yeah, fundamental science also deserves clusters of excellence. so the fundamental science that is the focus. And of course, if there is the potential of tech transfer, of course you will not be like, don’t talk to us in five years.
Speaker 3: No.
Speaker 2: So this is like 60 PIs, based only in Austria at the moment.
Speaker 2: Is it Quante or Quanta?
Speaker 3: it’s actually, we call it Quanta.
Speaker 2: Okay. It’s fun. I think it’s Quanta. Okay. Okay.
Speaker 3: I think we usually say quantum science Austria.
Speaker 2: It’s quanta. Now on, from now on, it’s quanta. It’s done. It’s official. Perfect. So 60 PIs in Austria.
Speaker 2: That is brilliant. That is the quanta. What else did you want to tell me about the quanta project? Oh, cluster of [00:31:00] excellence. Yeah.
Speaker 3: Of course, it’s not an isolated project, so each of us is collaborating, with people abroad. Of course, it’s just part, of the international efforts but bundled, at least Nostra, we want to make it a hub for quantum science.
Speaker 2: One stop shop.
Speaker 3: One stop shop for quantum science. And of course, we are communicating with technology. we know that quantum science can have applications and we are open for that. So there is, this interaction, of course, with our technological, oriented projects.
Speaker 2: Okay, that is perfect.
Quantour: A Quantum Light Journey
Speaker 3: If I move now from Fanta to Funtour, there’s a Funtour.
Speaker 3: So there it’s more, it’s more maybe towards technology. So we want to show there. That we have a semiconductor based source of quantum light, which could be used, for instance, for secure communication. And we want to show with this project that, that semiconductor, based light sources are [00:32:00] stable.
Speaker 3: So the source is starting from Berlin, and then it’s coming to Linz, and then we move across Europe and go back to Berlin. And I want to show that this is still working, and we want to perform measurements at different stations. And compare these measurements to see if they are compatible since, there is no standard, no standardized measurement protocol so far.
Speaker 3: So that’s the first step towards to go towards that.
Speaker 2: Okay. That is really good. And how has your experience been like? Tell me more about the, cause also Doris joined the handover and everything. How was that? How was that like with all the celebration and the sticker ceremony and all of that?
Speaker 2: How was that experience? Of course I’m also interested in the science, but you probably don’t want to talk about the science now because potentially this work will be published or most probably this work could be published, but, What was that experience like? Because you are the first contour hero from Berlin.
Speaker 2: You were the first stop.
Speaker 3: It’s an honor to be the first [00:33:00] stop. It has been a lot of fun up to now. So we picked up together with Maximilian Hagner, a PhD student in my group. We picked up Doris and Lucas at the railway station in Linz. And then we went through the city center, we made a stop to take a picture, and then we came to the university, and, Lucas and Maxilia wanted to load immediately the source in the cryostat and start measuring it.
Speaker 3: And actually, we had the occasion just in the same week. We had a workshop, it’s, the second, international workshop on Gallimard’s quantum dots. And so we took the source with us. we brought it to a very beautiful place here in Austria, which is Traunkirchen, with view on the Traunstein,
Speaker 3: The source went around also to some beautiful landscape here. up to now, it has been a lot of fun. So we made a speaker ceremony, in communication just next week. It was fun, and I think we’ll keep being fun in the future. Maximillian looks forward to [00:34:00] go to hand over the source
Speaker 2: to the next Contour Hero, which we will not reveal who it is.
Speaker 2: if you check out the website, you will know who the next Contour Hero is. So everyone watching, listening, if you’re curious, go to the science talk. com slash contour, and you will find all the heroes and everything there that is really cool. Are you also already starting to get ready to say goodbye to the source you and your team, or are you super attached to the source?
Speaker 3: I think we have enough, quantum dots. usually we produce billions of them. we are of course happy to have this one here So we look forward. the mission is to let this source travel. it’s just a continuation of a travel trip. it’s not a final goodbye. We keep seeing people around and then the source perhaps will visit one of the other colleagues.
Speaker 2: That is a very grown up answer. I have to say a very grown up answer. That is brilliant. Perfect. So then let’s shift gears and go back to your research experience as [00:35:00] a whole. It sounds to me that your research experience has been wonderful. if you had three wishes to improve your research experience.
Speaker 2: What would you ask for? And I’m not promising anything here. Three wishes.
Speaker 3: Yeah.
The Bureaucracy Challenge in Science
Speaker 3: Actually, I would have one wish. And that is that, I find that there is a lot of bureaucracy, which is pulling the brakes on science. To allow science to go on, we usually, apply for projects.
Speaker 3: And to get funding, both for the equipment and for consumables, but also, most importantly, to sustain the salaries of PhD students, to allow them to work and to create and to become the next generation of scientists. to the benefit of our society and industry. And, now this project application procedure, what I’ve seen over the last years is that it’s getting more and more, bureaucratical.
Speaker 3: So the formalities to apply for a [00:36:00] project keep increasing, and the pain doesn’t finish with the application of the project, but it continues during the course of the project where we have to write reports, And then it’s keeping increasing, so you keep having like formatting of CVs that must fulfill very specific guidelines and stuff like that, which has nothing to do with science.
Speaker 3: And all the time I spend and my colleagues all the world or across Europe’s spend in doing these things, it’s time which is lost from our real job, which is to create new ideas and to train people, the next generation, which is a basis for the well being, I think, in Europe. that’s a big pity.
Speaker 3: And that’s my wish. Less
Speaker 2: bureaucracy.
Speaker 3: Yeah, less bureaucracy. And give us back the time for the things we love and for the things we are trained to [00:37:00] do.
Speaker 2: I understand that this challenge or this pain is so strong that you just want less bureaucracy, lesser bureaucracy.
Speaker 2: No bureaucracy. No bureaucracy.
Speaker 3: the way, of course, there is need, of course, of a certain rules and certain frameworks. But at this stage, it’s too much.
Speaker 2: But Armando, this was your chance to put it out in the universe that you don’t want any bureaucracy. This was your chance.
Speaker 2: And you went super realistic and was like no, we actually need bureaucracy. Just a little bit.
Speaker 3: No, there must be some rules, but it’s going too far. So the bureaucracy and science are diverging. So the people, it seems not to understand each other anymore.
Speaker 2: Yeah. And it’s also right. I completely agree with you. This bureaucracy, it’s important, but it takes away from the fundamental, the core of your job and what you enjoy. And that just dampens the fun and. Sucks the [00:38:00] joy out of it in some cases and the resources.
Speaker 2: Exactly. I hope that we will have lesser, bureaucracy or better structures to support, professors like you I think we need to combine it both because it’s like lesser bureaucracy. But also support these kinds of bureaucratic tasks, which you don’t have to, or you shouldn’t have to do.
Speaker 2: but I’m confident that we have scientists like you who are aware of this and who are voicing it and who are, Also starting to become more and more decision makers in the system to change the system, so we will have lesser bureaucracy. The next generation of scientists will hopefully have lesser bureaucracy, fingers crossed for that.
Speaker 2: Armando, this has been wonderful. I have learned so much. This has been so much fun talking to you, but before I let you go, I have to ask you one last question.
Taking Over Real Scientists Nano Twitter
Speaker 2: And that is about your time, your one week on the Real Scientist Nano [00:39:00] Twitter account or X account, as we call it now, in addition to featuring, as a guest on podcast.
Speaker 2: Every guest will also get the keys to the Real Scientists Nano Twitter account for an entire week. So what can the followers, the more than 3, 000 followers that we have on the Real Scientists Nano Twitter account, what is the plan?
Speaker 2: What can the followers expect in the week that you’re taking over the Real Scientists Nano Twitter account?
Speaker 3: I think we will post, pictures of Our labs and, short movies of what we are doing in the lab and Linz and, The beautiful campus, here in Linz and the surroundings, Yeah, this is a, and some surprise perhaps.
Speaker 2: Oh, some surprise. So lots of, beautiful pictures, lots of lab pictures and people pictures and the science as well. I want to see the SEM images. of those bumps. I want to see. Okay.
Speaker 3: Okay.
Speaker 2: I want to see.
Speaker 3: We’ll do that.
Speaker 2: All righty. Perfect. And lots of pictures with the [00:40:00] source of the contour source, the Q source.
Speaker 2: Then thank you very much, Armando. This has been wonderful and excited to have you now on Real Scientists Learning. Thank you.