Agosta:It’s been a great experience teaching here. Over the years, I’ve taught a number of different courses. I’ve taught Introductory Physics, Electronics, Introduction to Quantum Mechanics, Energy in the Environment among others. Most of the classes are small. I don’t think I’ve taught a class with more than thirty students. It’s so much easier to get involved in the class, to know the students, and to feel like you’re really affecting the outcome of someone’s life. You really get to know the students you’re teaching.
Agosta: We study organic superconductors in my lab. These are organic materials that could almost grow on trees that you wouldn’t normally think conduct electricity. If you get some materials to a low enough temperature, they conduct electricity with no electrical resistance, so no energy is lost; they’re perfect conductors. The state of superconductivity is something that is almost unbelievable. If you start electricity going in a circle of a superconducting wire, it will stay going around that wire forever.
Interestingly, superconductivity was discovered in 1911, in Lydon, and we still don’t really understand it. Most superconductors today are still created somewhat by chance—we cannot design a superconductor. The microscopic theory of how superconductivity works is somewhat understood in a couple special cases, but a general theory of superconductivity does not exist.
Agosta: We try to understand superconductivity by studying organic conductors, since they are very useful systems to help us understand this area. One of the reasons for that is that organic materials are very complicated. So we work with organic chemists who adjust the materials, for example, the bond lengths and density of electrons in the material. Then, as we get different ideas about what might be causing some effect, we can say, “Why don’t you change this a little bit,” and then we see if it changes our measurements. From those iterations between changing the material and doing the new measurements, eventually we can get the connection between how the material is creating the superconductivity. As we say, “We have lots of knobs to turn” to figure this out.
Agosta: Our actual experiment is very dangerous because of the high voltage, so we are never in the same room as the experiment when the experiment is happening. The measurement we make is the radio-frequency penetration into our superconducting samples. We have a system where, it changes the frequency of a circuit, we measure that change in frequency, and we can work back to find out how much the radio frequency is penetrating into the sample. We need to make these measurements at extremely low temperatures in extremely high magnetic fields. As people hear about in physics all the time, we tend to make things not work to figure out how they work.
Agosta: Some serendipity is involved. When students come into the physics department they take introductory physics, start getting to know the professors, and at some point, tend to come around and talk to us and ask us what we do and if we have space in our labs. For example, we have one student who is interested in circuits and magnets. She asked if she could work in my lab, and now she is working on some high-frequency electronics, trying to understand where noise is created in the circuit. There really is a lot of opportunity for the undergraduates a Clark to get involved in the cutting-edge research that is going on at the university “graduate” level.