Nobel Prize Conversations

“You recognise opportunity and then you have to take advantage of it. Seize the opportunity basically. It takes some struggle.”

Some words of wisdom from chemistry laureate Louis Brus. In a conversation with podcast host Adam Smith, Brus speaks about the process of discovery and his own scientific path.

This conversation was published on 27 June, 2024. Podcast host Smith is joined by Clare Brilliant.

Below you find a transcript of the podcast interview. The transcript was created using speech recognition software. While it has been reviewed by human transcribers, it may contain errors.

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Louis Brus: If you studied engineering or science, it was seen as patriotic science and engineering helped us win World War ii. There was a period of time in the 1960s where many corporations thought that PhDs could do anything.

Adam Smith: It’s fascinating to listen to Louis Brus speak about what was really a different time in science, and I think a sense of duty sort of pervaded his career. But these days, I don’t think that concept comes into the equation when talking to young people about going into STEM subjects. And maybe they should, and perhaps it’s not a patriotic duty. Maybe it’s a global duty, given that the humanity and the planet are faced with so many seemingly insurmountable challenges. It’s also interesting to hear him reflect on the idea of being encouraged to do anything with a PhD. His own training exposed him to so many different spheres of science, and that’s obviously stood him in terribly good stead as one will hear. So do stay with me to explore Louis Brus. 

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Clare Brilliant: This is Nobel Prize conversations. Our guest is Louis Brus, the 2023 laureate in chemistry. He was awarded the prize for the discovery and synthesis of quantum dots. He shared the prize with Moungi Bawendi and Aleksey Yekimov. Your host is Adam Smith, Chief Scientific Officer at Nobel Prize Outreach. This podcast was produced in cooperation with Fundación Ramón Areces. Brus is the Samuel Latham Mitchell professor Emeritus of Chemistry at Columbia University in New York City. In this conversation, he talks about how he found his way into science by serving in the Navy, and about the moment he realized he wasn’t cut out to command a battleship. But first, let’s hear about some of the perks of being a senior scientist. 

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Brus: It’s hard to think about new things when you have a big group and you have contracts that obligate you to do certain kind of research, and you have to monitor the progress of everything that’s like a business and you don’t have much time to think about things coming out of the field or things that may have been invented since you were a student. 

Smith: That’s such an important point that you need time for reflection. 

Brus: Yes, I’ve been studying things now that I was always too busy to actually work on mostly biological issues and genetics and so forth, just trying to understand the state of the art. 

Smith: Your curiosity leads you. It’s the perfect way to approach research. 

Brus: Yes, that’s right. 

Smith: People complain a lot that nowadays nobody has the time to reflect, especially young people. Their phone is constantly delivering information. It’s just a 24/7 environment. But actually, when you were a child at school, I don’t think you had all that much time to reflect. Your father made you work as well as going to high school. It was a busy life. 

Brus: It was a busy life, but it did not strike me as a bad thing, let’s put it that way. I was very good at academic subjects and homework and all of that didn’t take much effort on my part. Most homework could be done during the free time in school itself. I was able to work in the hardware store and actually I had a second business cutting lawns in the local neighborhood. It just seemed like the way humans normally operate. It’s very different now in some wealthier suburbs of New York and in the United States. These students, they have all these extracurricular activities. They’re being tutored for college exams and working in a store is not on the radar. 

Smith: But apart from the money it brought, which I’m sure was handy, the experience of working in a different environment was helpful. 

Brus: Yes, for sure. The guy who ran this hardware store was a Russian Jew. His father had come over from Russia and he was a very tough character. He had been a Marine in World War II and he was really mad at Truman because when the Korean War came, Truman sent the Marines into Korea and he called up the reserves. This guy, Alex Por, he was called back into the active duty of Marines. That was the last thing he wanted because he was running the hardware store and he had a very abrupt and abusive way of dealing with the salesman who came by from the wholesale hardware companies. They were trying to get him to buy things. He worked hard and you could see he had to deal with customers and the customers would also say stupid things, but he had to grin and bear it and not get mad. 

All of this tended to have a short temper, but I learned how to do all this stuff. My father was not adept with tools and didn’t repair things in the house and all of that. I learned that in the hardware store. That’s good for an experimentalist because I was always theoretically inclined. I went into science because of the ideas, not because of the machine I was going to build, but just experience in the hardware store just gave me the fundamental foundation to deal with the apparatus that we had to build as time went on. 

Smith: Yes. It sounds like it gave you the ability to deal with apparatus and also with people to a certain extent. 

Brus: Yes. There are all kinds of crazy people come in as customers and you have to work with each of them. 

Smith: Because something that turns out a scientific career is also about socialisation. It’s getting on with people and filming collaborations and that’s another skill you have to develop.  

Brus: Basic research. It’s less important than in other walks of life, but still it’s important. You need to be able to work with students, you need to be able to work with colleagues, make collaborations and so forth. 

Smith: It sounds like you had happy schooling days and then a happy time at Rice when you went to college as well. 

Brus: Yeah, Rice was tough. It was a heavy course load and it is true. We had lectures six days a week. We went for lectures on Saturday morning, and I tell these stories now to my undergraduates and they just are amazed. But I liked it very much because I was well fit for the course load down there and so forth. 

Smith: Was it clear to you even at that stage that you wanted to make a life in arts because you had gone to Rice as a Navy scholar, you were also in the Navy at the same time? 

Brus: No, it was not clear. It wasn’t really, in my mind, it wasn’t possible for me to be a scientist as a boy in high school or as an undergraduate at Rice. In fact, in those days there weren’t that many scientists after the war. There were more coming up all the time, but it was only towards the end of my time at Rice at this in my mind, became a real possibility. But it was linked to the fact that I had to go on active duty with the Navy. There was always this complication. 

Smith: Complication, but also how amazing to have the experience of stepping from the academic world of a high pressure engineering school to being out in real life and serving on destroyers and aircraft carriers. 

Brus: Yes. That was a much better experience for me than working in someone’s lab for the summer, basically. 

Smith: It must have been amazing. 

Brus: Yes. I was in a midshipman program that was supposed to produce career naval officers after college. Because of that they rotated us through all these different aspects of the Navy during the summers, three weeks here, three weeks there, seven weeks on the aircraft carrier and all of that. Extremely vivid memories of all of that. 

Smith: Were you tempted by the career? 

Brus: Not really, because I recognised that I wasn’t sufficiently a leader and I had introverted personality and I would be good for technical things, but not for leading 300 men on a destroyer or something like that. Some people have a natural gift for leadership. When I was in training in the Navy, I saw two or three of these captains who were just marvelous people. The morale on their ship was a lot higher than it was on other ships. The way of organising, and it’s the same thing in business. There are some people in business who are very charismatic leaders and get more out of the operation than others. Politicians are like that. Politicians have to know when to be at the right place at the right time and to pursue an idea not too early when people won’t accept it. Anyway, there’s all these calculations going on. 

Basically I had a leave of absence from the Navy for four years in order to earn a doctorate before I went on active duty. I was in the Navy, commissioned to the Navy, but I was put in the reserves for the four years so that I could attend graduate school full time. Then I looked around the country and I applied to Columbia because it had a chemical physics program, which was more to my liking. Very lucky there. Lucky that that opportunity came at the right time for me. Otherwise I would’ve probably ended up as an officer on a nuclear submarine, or I would’ve been an instructor in the nuclear power school or something like that. At the end of my time at Columbia, I was also very lucky because it just worked out through circumstance that I was able to be assigned to the Naval Research Lab rather than assigned on board ship. 

That’s because I had a PhD at that point, a new PhD. They didn’t know what to do with me at the Naval Research Lab because they had not had officers coming in with PhDs before, scientific staff officers. I was like an extra person floating around and they maybe paid my salary, but I didn’t have a lab or I didn’t have research money, but I was able to join basically different groups in different divisions to work on things that were of interest to me. So I finished at Columbia and then I went to the Naval Research Lab and I realised I was very lucky to be there. It was also an opportunity at the same time in the sense that I could learn these new things, take part in the research without actually having to write a contract and build a group and so forth. Just sort of like being a postdoc. My training was in molecular chemistry, but the Naval Research lab was far broader than that and had all these engineering aspects and I attended some classified seminars and many seminars in physics and material science. That was good. 

Smith: Were they happy for you to be basically asking fundamental questions? 

Brus: The NRL was the most basic of the various. Navy had many different facilities across the country, but the Navy had a substantial basic research effort in the Naval Research Lab in this one location. They were supposed to basically keep track of science and look for things that happened that might impact the Navy discovery made somewhere and maybe this could be used for solve a problem the Navy faced. They had bigger efforts in certain areas, obviously had a huge section on radar, fundamental principles of radar and electromagnetic radiation, had a big section on the surface science and fundamentals of how to protect the steel ship in the ocean. Big section on the engineering of on a nuclear submarine, you have to process the atmosphere. This carbon dioxide is building up, you have to take it out and it has to be. 

They had a very big section on the basic science of how to deal with gases in the atmosphere. They tried to build up first class efforts in the areas that were particularly relevant to the Navy. Obviously Navy is the most technical of the various services. Everything is a complicated machine on onboard ship. As time goes on, there are fewer and fewer jobs that involve manual labor and more and more jobs on board the ship that involve, you have to be technically trained, operate this complicated apparatus, months of training before you can go on onboard ship. There was huge technical operation. 

Smith: That sounds like you made absolutely the right decision to have been part of the Navy as you went for your undergraduate course. 

Brus: Yes, I don’t know that I had it in mind when I was in high school like that, but anyway, that’s the way it worked out. 

Smith: Why did you choose the Navy? Do you remember why? 

Brus: It was mainly because my father had been in the Navy in World War II, so I had to choose one of them. I’ll choose the Navy. 

Smith: How much influence do you think it had on you growing up at that particular time, the Cold War going on technological developments like Sputnik happening around you and garnering a lot of excitement?  

Brus: Similar to now, basically, so now the government very strongly encourages STEM education. It’s good for the country and good for the economy. At that time, if you studied engineering or science, it was seen as patriotic. People would always say the Soviet Union has more engineers than we do. It has more medical doctors than we do. We need to build up this strength. There had been all these improvements in society and in due to science and engineering, science and engineering helped us win World War II. This was very important for the economy. There was a period of time in the 1960s where many corporations thought that PhDs could do anything. They had no experience with research, they just were ordinary businesses. But they thought if they hired two or three PhDs and let them loose, they would make one marvelous invention after another help the company, you know, that failed, obviously. But we went through a period where that happened basically. 

Smith: I can imagine people try to tempt your away, but you found your way to Bell Labs, and that’s a legendary place, which people talk about a great deal, and many have tried to emulate the research environment there. It must have been such an extraordinary environment because you had no particular directive there. Just a bit like at the Naval Research Labs, you were free. 

Brus: They wanted you to create your own program, but it had to be in the context of the subjects, again, that were important to the telephone system. They did not have a big program in biology. As time went on, they developed one department, but that was like one department out of 40 departments or something like that worked on biology. You worked in a certain area and you were supposed to invent new things, just like the Naval Research Lab, invent new things. The main thing that would come out, that would be a very valuable patent if you’d figured out something in advance. It was a very valuable patent. That gave some economic leverage to it. But it was a curious situation in the sense that because it was more like a federal laboratory than it was a corporate laboratory, because it was a regulated monopoly. Part of the regulation was that at and t could write these valuable patents, but they were also forced to license the patents to companies in the US who wanted to use them because the patent had been developed using money from their regulated monopoly. Everyone had to use the telephone system. It was a great research operation and it made for a very strong telephone system. But it was not a great money making operation. No one got rich from it, let’s put it that way. 

Smith: No, but an awful lot of discoveries poured out. 

Brus: That’s right. Great place to do physics. 

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Brilliant: Here we are again, Adam, with another Nobel Prize. What did Louis Brus discover? 

Smith: He discovered quantum dots, which have become a very big deal. Back then what he found was that some particles he was studying, some particles of semiconductors seemed to change their properties depending on their size. That was truly remarkable because physical properties aren’t supposed to change his size. If you’ve got a lump of something and it’s the one size or another size should behave the same. But in this case, when you get down to very small sizes, things begin to behave differently. He recognised that that was very interesting. Something was going on. 

Brilliant: He must have been really surprised and excited. In what way did the properties change? 

Smith: He was studying a semiconductor called cadmium sulfide, and he was studying it in a colloid. 

Brilliant: What is a colloid? I sort of vaguely recognise that term from school chemistry lessons, but I’d love a reminder. 

Smith: A colloid is just a suspension of tiny materials in liquid. Most common example we encounter on a daily basis perhaps is milk. Milk isn’t a solution. It’s a colloid where little bits of protein or fat or phosphates are suspended in this material, which makes it opaque. He was studying a colloid of cadmium sulfide in a car liquid. When he shone light on that, he found that the particles absorb light differently depending on how long that colloid had been standing. He worked out that what was going on was that the particles were aggregating over time and getting bigger. Depending on their size, they absorbed light differently. That shouldn’t be happening if things behave the same at different sizes. But it was, and he studied it. 

Brilliant: If different sizes were absorbing light in different ways, how did this present itself? How did he observe that? 

Smith: He observed it in the absorption spectra of the particles. But what he worked out was that these dots, these little particles were behaving as described by quantum mechanics. Quantum mechanics predicts that very small sizes, there’ll be discreet sets of energy levels in particles that are governed by their size, and they would result in different sorts of absorption spectra. With much refinement and study that’s gone on to produce a whole world of different quantum dots of different colors. But back then it was just a first observation. 

Brilliant: What made him decide to sort of follow through on that observation and take it further? 

Smith: He saw that he was seeing quantum mechanics in action, if you like. That’s what he was interested in. He was interested in the physical manifestation of principles that are all there in the textbooks. That’s what first attracted his attention. Then I think quickly he realised that this could be applied. The remarkable thing is that he took notice and followed it up. It’s very interesting to hear him talk about that. 

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Brus: Often there’s an element of luck in that, that’s his famous quote, luck favors a prepared mind. There’s certainly truth in that. Most discoveries are made by people doing research in a more or less straightforward fashion, but then they stumble into something unexpected in the lab and they can either ignore that and continue on the original line of research or they can take a risk and try and work on this unexpected thing, which you don’t know what’s going to come out of it and whether you’ll make much progress and whether you could get it funded. It takes a lot of courage to go into new areas. Some people have the natural personality for that and others don’t. 

Smith: But obviously your particular question, which I think it’s fair to say, has defined all your work of just asking what the electrons are doing. 

Brus: There were lots and lots of scientists who were basically doing that. Everyone in solid state physics and everyone in chemistry at some level is you have to deal with the electrons either in molecules or in solid state. That was my original training. I spent all this time studying quantum mechanics of molecules in graduate school and spectroscopy. That’s evolutionary. I was like 12, 14 years out of graduate school before I started to work on the quantum dots. There’s a long evolutionary pathway from finishing graduate school to the point where I began to work on quantum dots. When I got down to the working on quantum dots, nobody understood what I was doing to begin with bcause I was a member of this community of people who were doing ultra fast laser spectroscopy on molecules or doin and trying to use fancy spectroscopy to study chemical reactions. Nobody in the world was working on colloids. This was a completely dead subject. It had been popular in the early part of the last century. 

Smith: I wanted to ask why you made that switch to colloids at about 12 years out of graduate school?  

Brus: Part of it for sure was I recognised that this was important for Bell Labs. I had the opportunity, so the management supported me. I didn’t have to go to the NSF and convince them or convince reviewers that college were important. I just needed to convince the management of Bell Labs. They understood that these small particles represented the future of microelectronics in some sense, it might be 20 years out, but the driving force in the whole business was the fact that transistors were getting to be smaller and smaller every year. That was the driving force for the entire industry for the last 50 years or ever since 1970. At some point they’d get to be so small, they would behave more like molecules and they would not behave like bulk transistors. Then the industry would have to adapt to the fact that this silicon was behaving differently at small size than big size. 

This was not necessary yet when I started in the 1980s. But any intelligent person could see that it was coming down the horizon. It might be 40 years away, it might be 15 years away. But anyway, this was recognised as long range research relevant to the computer and communications industry. It was just one person. Me. It’s a question of how important is it versus how much money do you have to invest? So if Bell Labs make a development effort, they might be 15 or 25 scientists. That’s a big expense, you know. But if it’s just a research project carried out by one guy with his own hands, let him go and see what happens. 

Smith: They got their award for backing you. It does sound like an absolutely perfect environment to be with people making decisions above you based on your track record and also with an extraordinary timeline in in mind, not thinking about any benefit.  

Brus: A lot of the people, most of the people in South State physics were thinking of very long timelines in superconductivity and a correlated electron behavior. None of that was relevant to the present transistor design and so forth. There was just new areas of solid state physics they weren’t uncovering. Again, it wasn’t clear that any of this could be made into devices. The idea was you would discover something brand new that people didn’t realise and then you would sit and think a little bit about where it might be relevant or if it might be relevant. Then if there was some obvious relevance, the management might want to make a development effort out of it, but maybe not. Anyway, come up with new ideas. It had worked, the laser was such an invention, basically took a long time to figure out what the laser was actually good for once it was invented. A different thing was the transistor. The transistor had been a real effort by the telephone system to make better equipment. They put a team together to make solid state switches rather than continue with using vacuum tubes like they had for the first half of the century. But again, that takes money. You don’t know that it’s going to work and we have to fund all this. 

Smith: But that’s more of a moonshot program where you put the resource in. 

Brus: Moonshot required many hundreds of people to build a rocket. But this initial research on transistors was like three people and they didn’t know quite what they were doing. Nobody knew how to do this, how it was possible. They didn’t understand the principles of semiconductor physics. They stumbled around for a while and then finally made a device that worked a little bit. The managers of the corporation could understand that this might be very important because they were struggling with the present equipment. They were struggling with the fact that the system used vacuum tubes and microwaves for long distance transmission. They’re looking for the system we have now using fiber optics and light propagation carry all kinds of communications that’s far better than what we had when I was just starting out in Bell Labs. Completely changed the world. All of that comes from basic research that people think about and then decide how to use it in the present day. It’s entrepreneurs who start new companies in order to make money. 

Smith: I really like the phrase you used that they didn’t quite know what they were doing, because that’s such an important point to get across to everybody about trust in science, that it’s not as if you can fund people to get to a definite end. You have to fund people who don’t quite know what they’re doing. But on the other hand, you have to trust them that they’re sort of heading in the right direction. 

Brus: No, you make a judgment that they are creative and this happens based on what they’ve done when they were younger. You make a judgment that they’re ambitious and so they would like to make a great discovery. They’re kind of always looking for, it’s not just a job, it’s their entire life, basically. Some great projects, for example, there is this infrared telescope that’s in outer space, won the Nobel Prize. That’s a great achievement, but that’s not an accidental discovery. That’s a great big engineering project involving hundreds of people. That $10 billion budget that everyone knew that if it worked, it would revolutionise the data you got on the universe in chemistry and in biology and in material science. It’s not like that. It’s one or two people working on a project that stumbled into something unexpected. This CRISPR business for the editing of DNA, that’s an unexpected. After working on it for six months or a year, they realised they might be able to actually monitor change the DNA and all of that. 

Smith: When you came across colloids and you dedicated your research to that, and you came up with the first quantum dots simultaneously with those in Russia, but you didn’t know that that was happening, do you remember the feeling of particular excitement that you’d managed to make quantum mechanics visible in this way? 

Brus: It was an accidental discovery when we first saw the spectrum beginning to change because of small size, make particles smaller and smaller. Spectrum looks the same all those time, and then all of a sudden when you reach a certain size it against a change. New peaks appear that I realised was important, but I was more focused on the fact that to make progress, we had to make better particles. I’m a spectroscopist interested in quantum mechanics, but to make progress we had to focus on synthesis. That was a long struggle. My mind kept thinking all the time about how lousy these particles are. I just wish I could find a way to make them better in all of this. At the same time, my position in the labs was stable. They’re quite happy, as I said, for me to one or two people just to work on this project. I come from the academic chemistry community of research, basic research, and I wanted to convince them that this was an interesting project. What I had to do was go around the country and give colloquial different schools over time telling them what I was doing and then trying to explain why this was interesting to be part of chemistry. Chemical research takes time for people to accept the ideas. 

Smith: Sure. If you’re sitting on something that’s so novel, how do you balance the desire to tell people about it and to get everybody excited with the possibility that then people will run off and do the same thing and suddenly you’ll increase competition? Or is that not an issue? 

Brus: If people begin to copy you? But it’s the old cliche that’s the most sincere form of flattery. I would be happy with that. My whole life I worked on subjects and then when the field got to be too crowded, if there’s a well-recognised problem in science and strong academic groups all across the world are working on this project different ways, everyone recognises this as an important project, then it’s hard to make progress. That’s not a good field for a young scientist to go into because the competition is so stiff, much better to find a project that nobody else is working on that somehow is important and you’re in the right place at the right time in the right institution where you have the resources or the opportunity to actually pursue this curious project. But you can’t really invent this from scratch. It typically comes from unexpected observation in the laboratory that causes you to sit down and think about things. 

Smith: When you first produced quantum dots, when you then learned that there was similar work going on in Russia, you tried to reach out across to the Soviet Union to make contact. But that was hard, wasn’t it? 

Brus: I sent a paper, I found these papers in the Russian literature, eventually translated into English, and I realised they were working on the same thing, the different high temperature glass and the different materials and so forth. I wanted to make contact, particularly with the theorist in Soviet Union Afros. This is common among scientists. You make contact with other groups around the world that might be interested in the same thing that you are in time. I sent a letter and I think plus one of my publications, just a reprint of a paper that I had written into the Soviet Union, just to show him what we were doing. That worked out fine. It took another five or eight years before Afros could come out from behind the Iron Curtain. The Soviet Union was beginning to collapse, and the strongest scientists in the Soviet Union were leaving one by one and trying to find some kind of position in the West Europe or in the United States to continue research. Russian science today is the weak shadow of what it was when I was young, because the Russian government put so much money into basic research because it was relevant to the weapons program. But now it’s collapsed, basically. 

Smith: It’s tragic, isn’t it? They’ve disbanded the National Academy of Sciences there and everything. 

Brus: It’s taken up by the Chinese. The Chinese have just done the reverse. Chinese have gone from complete poverty to being very strong. They recognise all these arguments you and I have been discussing here. China is a country that has no natural resources. They have intellectual resources and manufacturing, basic science and all of that. 

Smith: I know you read a lot of history. Do you find historical parallels in what you do, figures in history, who you relate to? 

Brus: If you read the details of the famous people of history, Lincoln and Churchill and Eisenhower, things like that, what was always striking to me is that they made a lot of mistakes as well as doing some good things. Maybe 25% or 40% of the things they tried were stupid. They were not that much smarter than everyone else. They were just driven to find something that worked, basically. 

Smith: It’s a nice idea to feel that somebody like Lincoln is approachable. 

Brus: I kept telling people that he did not control events, but events controlled him. That was true for the entire length of the Civil War. He was this country lawyer who all of a sudden became president and a very ambitious man, but still country lawyer, a politician in Illinois. But he was good with dealing with people because he’d spent his whole life on the law circuit in court trials and things like this. He had a very good understanding of the range of human people and how to build an organization and so forth. He was in a place where he had to act when he became president. He had no idea that he was going to be in this long, hard war, that 600,000 people would die and almost destroy the country. Nevertheless, he had to deal with it. Churchill got into power just when everything was going to hell. Any rational man would have tried to negotiate with the Germans, rather than continue the war. But he was steeped in British history. He’d been in the army as a young man, and he wasn’t going to give up easily. He was of a mind that he would rather fight and die than negotiate with the Germans and live under their control like that. Even if it meant that a lot of people would die. 

Smith: I suppose the lesson one learns from them is that it’s necessary to rise to the occasion when it presents itself. 

Brus: Almost every great person is like that. You recognise opportunity and then you have to take advantage of it. Seize the opportunity basically. It takes some struggle. 

Smith: It takes struggle and strength and the good fortune to be in the right position that you can devote yourself to it. That’s a wonderful point to end on. Thank you very much. 

Brus: Yes. Thank you for calling me. 

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Brilliant: You just heard Nobel Prize Conversations. If you’d like to learn more about Louis Brus, you can go to nobelprize.org where you’ll find a wealth of information about the prizes and the people behind the discoveries.

Nobel Prize Conversations is a podcast series with Adam Smith, a co-production of Filt and Nobel Prize Outreach. The producer for this episode was Karin Svensson. The editorial team also includes Andrew Hart, Olivia Lundqvist, and me, Claire Brilliant. Music by Epidemic sound. If you’d like to hear from another laureate who relishes the challenge of the unknown, then check out our episode with 2022 chemistry laureate Barry Sharpless. You can find previous seasons and conversations on Acast or wherever you listen to podcasts. Thanks for listening. 

Nobel Prize Conversations is produced in cooperation with Fundación Ramón Areces.

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