Fri October 12, 2012
Fifty Years Ago, A Bright Idea
Originally published on Fri October 12, 2012 12:45 pm
IRA FLATOW, HOST:
This is SCIENCE FRIDAY. I'm Ira Flatow. Fifty years ago this week, a team of researchers at General Electric created something new: a solid-state device that could emit visible red light without getting hot like a light bulb. Other groups have made light-emitting devices, but this was the first practical one that could make light that a person could see, rather than invisible infrared light.
That work by Nick Holonyak and colleagues went on to be the basis for just about every LED starting back - staring back at you, you know, those little red lights on the little devices? This was the first one. Nick also did pioneering work on other electronic devices, including lasers. And when the Applied - the journal of Applied Physics Letters drew up a list of the five most important papers it had published up to 2006, Nick's name was on two of them. And he's here to talk to us now.
Nick Holonyak is the John Bardeen Endowed Chair in Electrical and Computer Engineering and Physics in the Department of Electrical and Computer Engineering, University of Illinois in Urbana, Illinois. He joins us by phone. Welcome back to the program, Nick.
NICK HOLONYAK: Thanks, Ira. You and I talked about this stuff in Washington when the MIT Lemelson Prize was given. Remember? And so this is our second contact, maybe more.
FLATOW: I'm hopeful we have a lot more to go, and I want you to - let's talk about this 50 - the anniversary.
HOLONYAK: Well, it's October 9th, I put - my colleague in Schenectady, Bob Hall, beat me with gallium arsenide, which is much simpler. And I wanted - I shifted my crystal system to the red and made a homemade alloy, gallium arsenide phosphide, and you are absolutely right, that was the first one that anyone could have - they could buy it at an exorbitant price from GE at the time, but it started off as a laser. And that's just a special form of LED that says this is a very powerful light source, and I knew from that, uh-uh, this is going to go, go, go. But of course I didn't know it would take 50 years of work to get to where we are now.
FLATOW: Lasers were pretty new at that time, right?
HOLONYAK: Oh yes, in fact the conventional laser was only two years old, and it taught us that light could be coherent. But it didn't say anything about a semiconductor and whether the semiconductor would do this. And actually the furor started with Rediker's group from Lincoln Laboratories, MIT, reporting that they had gotten good spontaneous light out of gallium arsenide.
And then several of us went home and realized there ought to be a way to make that coherent, into a laser, and we did it. And - but I'm the guy that was crazy enough to make my own homemade alloy, which a lot of people didn't think would work, and shift it up to where the eye could see. And that's the whole basis of it.
FLATOW: Ah, did you - why did it take 50 years?
HOLONYAK: Well because these crystal systems are complicated, how to grow them is complicated. There are wrong methods and arguments about right ways to proceed, and it just - it's a zig-zag process. You make a bad move, and then you're going to make another move to find your way, and it just took a long while to get there.
And you had to - as you made progress, you're shifting into more complicated crystals as you go higher in the Periodic Table of the Elements to get the lighter elements that will shift you to higher energy and to shift the color from red to orange to yellow to green and then blue. And still, green and yellow still a problem, but, well, we're learning. We're getting there.
Oh, and one other thing I should mention. If you study this carefully, you find this is an ultimate lamp. It's right in the current path that the light is being generated. It's not some kind of secondary process where you heat up something or have a gas discharge, and then the energy is shifted to some other process, and then finally you get light.
No, no, this is right in the current path from one terminal to the other, right in that path is the process that generates the light. It's an ultimate lamp.
FLATOW: Is that why it works so efficiently?
HOLONYAK: Yes, and that's why you know that as we get smarter and smarter dealing with complicated materials and get to where we're going, the only loss will be ultimately just ohmic loss, resistive loss because when you move charge you're going to get some resistance, and that's going to be lost.
FLATOW: Do you still have that first...
HOLONYAK: Yes, yes, in fact three weeks ago, General Electric came here because they now realize that this is coming with a vehemence and changing - that all the lighting is going to be this. And of course they've got a lot of pride in this, and they could use it for their purposes.
So they came here and filmed one morning. I was pretty rough on them, in a sense, because I said I'm not going to do anything special for you guys. I believe in you, I've worked with you and all that, but just come in here with your stuff and film. And so it's in my drawer here.
FLATOW: It's going to be - you're not giving it to the Smithsonian or anybody like...
HOLONYAK: Hey, Ira, it's a tiny little crystal, and it's hard to believe that a tiny little crystal, you tickle it with a current, and wham, it'll blind you. In other words - I don't really don't know what ought to be done. You know, John Bardeen didn't give his first transistor box to the Smithsonian. It's here in a museum, and I don't know. That's an interesting question: Where should things like that go?
FLATOW: But were you worried when this little thing gave off some light that it might blind you? I mean, you didn't know what would happen.
HOLONYAK: Yes, yes, but then an expert in light, Zernike, a famous name, started in Europe, his son came from Connecticut, from Perkin-Elmer to see my first lasers, this red stuff, at GE in Syracuse, and I said: Watch out, Frits, you're going to hurt your eye.
And he laughed, and he said no, Nick, since it's visible, and the way this thing has a pattern, I can come into it from the edge, and I can tell right away when I'm overloading my eye. So if you're experienced, you won't hurt yourself. But it's true that if you don't know what you're doing, yes, a laser can hurt your eye.
FLATOW: Didn't you also invent the laser diode that's in all the CD, the DVD players?
HOLONYAK: That was the basis for this.
FLATOW: It's everywhere.
FLATOW: I hope you got a lot of royalties from all this.
HOLONYAK: Whoa, no, it doesn't work that way, Ira.
HOLONYAK: And no, I got enough to...
FLATOW: Did you get a dollar? Did they sign it away for - did you sign your rights away for a dollar or something?
HOLONYAK: At Bell Labs you sign it away for a buck. And in the group I was in at GE, they give you share stock and a little bit of cash so you can pay the IRS because it would be unseemly to get - to have to pay for something that's a gift that's considered income.
FLATOW: So where did you enjoy - or compare the places where you worked. You worked with John Bardeen in the invention of the transistor at Bell, and now you worked at...
HOLONYAK: No, no, I worked with John, he had already come here, and I worked with John, and then I went to Bell and worked with John Moll and then later was in the Army in a group they won't let me talk about too much, it was an intelligence group in Japan.
And then when I got out, I was six years at GE, and that's where this happened. And then I had a fantastic colleague there, Bob Hall. Bob's getting a little bit old, but he was a stalwart figure. He would've been the next Nobel Prize I would've given in the semiconductor field.
But I had access, you're right, to some of the very, very best people that were pioneers.
FLATOW: It must have been very exciting during those times.
HOLONYAK: Yes, yes, and incidentally, I'm with some very good people now, and we've converted the transistor into a laser. In other words, we've got a transistor that's still a transistor, but it's also putting out a laser signal. And I'd like to live a little bit longer, and I'm beginning to get a little bit frail, and boy, there's a lot of fun stuff to do yet.
That ought to be a message to your young people to get going. Get in school and start making something happen because if an old guy tells you he did it all, he's lying.
FLATOW: So you're talking about Milton Feng and the transistor laser.
HOLONYAK: Yes, yes.
FLATOW: What does that do, the transistor laser?
HOLONYAK: It - his transistors are the fastest transistors on Earth, hundreds of gigahertz, and there's a lost signal in there that's important to the operation of the transistor, and it turns out it's not generating heat, it's generating light, and you can arrange it inside to help it a little bit and turn that light into coherent light.
So now there's a coherent electrical signal and a coherent optical signal, and this is going to be the basis of some fantastic chip, and boy, I'd like to see some of that. But I don't - it's going to take a long time, Ira, because these are complicated things to do and complicated to make, and well, it just takes a while to learn it all.
FLATOW: Did anybody foresee the ubiquity that the LED would turn into when...
HOLONYAK: Well, I think all of us knew yes, it's a light emitter, but we had bitter arguments with various people about which crystals, how to do this and all that. And I feel good because I was on the right side with the kind of crystal I was doing and in fact told the Reader's Digest writer back then that this is the basis to go in the direction of LEDs in the practical world.
And in the February 1963 Reader's Digest, you'll find that he quotes me for that. So I'm taking a little bit of credit, but I didn't - I did only a piece. The other folks added a lot to it, including students, my students.
FLATOW: Do you think if Thomas Edison had still been around, he would have understood what you were talking about?
HOLONYAK: No, because he did not have the right kind of training, and I think that's the basis of some of his arguments with Tesla. Tesla had more of a scientific base, but Edison was a fantastic inventor. But I don't think - well, the bulb did a lot for a long time, but it can't last. It just can't last. It's not based on the right mechanics.
FLATOW: Is there a bulb beyond the LED, do you think? Is there something next?
HOLONYAK: Well, I think - what I'm talking about is ultimate. Now you may find some further versions of it, but you're never going to exceed it, because in principle, this thing can be 100 percent efficient, 100 percent conversion of electrical energy to light energy.
HOLONYAK: There's some practicalities like the ohmic loss, the heat loss from current.
FLATOW: Right, but 100 - well, you mean 99.999...
HOLONYAK: Well, no, no, wire loss, contact loss, stuff like that, you know, and in other words if John Bardeen had gotten the superconductivity to come up to room temperature, and we could get a lot of the wiring done with superconductors, then we would get all the way to 100 percent.
FLATOW: I understand that there was a cake this week with 50 LED candles.
HOLONYAK: Yes, yes, and I was inundated with students and visitors and all of that because there's a fascination to this, and they all - well, they're all happy to be - to see something like this and realize that when I started and where I started is where they are and that they can do something. And that ought to be the goal: school, learn and then use your own abilities to go further.
FLATOW: Do they realize that? Do they understand that?
HOLONYAK: I know some did. Now others I think are still thinking I'm going to quickly grab a degree and get a fantastic job and get rich, but I don't think they're thinking beyond getting rich. Now I don't know if that's a good life.
FLATOW: Well, congratulations to you, Nick.
HOLONYAK: Thanks, Ira, thanks and boy, you sound like a young man yet, so...
FLATOW: Thank you.
HOLONYAK: It's a pleasure to talk with you.
FLATOW: You made my day, and I hope to speak with you for many more years to come.
HOLONYAK: Thank you.
FLATOW: Congratulations. Nick Holonyak, John Bardeen Endowed Chair in Electrical and Computer Engineering and Physics in the Department of Electrical and Computer Engineering, University of Illinois in Urbana-Champagne, whichever way they keep switching those names back and forth over the years.
We're going to take a break, and when we come back, we're going to talk about the Nobel Prize winners announced this week, some interesting stuff. Get your geeky hats on again because we'll talk in detail if you'd like. Stay with us, 1-800-989-8255 is our number. We'll be right back after this break. I'm Ira Flatow. This is SCIENCE FRIDAY from NPR. Transcript provided by NPR, Copyright National Public Radio.