James Logan is a graduating senior writing a physics thesis. A double major in physics and mathematics, he is also a member of Spectra, the college’s physics and astronomy club, and will be attending Dartmouth College for graduate studies in physics. His advisor is Chair of Physics Jonathan Friedman.
Q: When did you decide on your majors, and what led to that decision?
A: Back in high school was when I really got interested in physics. My junior year, I had a great teacher for my first physics class, and [in my] senior year of high school, I took AP Physics. And at that point, I decided, “Maybe this is what I want to do, it's very interesting.” Every day I went to that class, I was excited and engaged, which I couldn't say necessarily for every other class I was taking. And so I just decided, why not go ahead and try for physics?
[When] I got to Amherst, I took a different route. Because I had taken AP Physics in high school, I started out with modern physics here, which is usually a sophomore level class. A few other people in my class here did that as well. This was before they had the new [“Oscillations and Waves”] class to dump people into if they tested out of mechanics. But I didn't actually declare my major until sophomore year. I wanted to wait a little while just to be sure that it was what I wanted to do.
And then actually [in] junior year, I declared math as a second major. I took a great class with [Professor of Mathematics] Amalia Culiuc. She's one of the newer professors in the department. Sheswitched me [over] from someone who had a bad experience with math here and[had] thought, ‘You know, I'm never gonna take math here again’ [to] a math major.
Q: Can you describe your thesis?
A: My thesis centers on molecular nanomagnets, which you can think of as really tiny magnets — like a bar magnet [with a] good old blue and red cartoon with a north and south. It's a little more complicated than that, but at a basic level, that's what it's like. And we think those sorts of systems would make great candidates for qubits, which are quantum bits.
[A qubit is] the quantum analog of a classical bit, which is the information storage used in classical computers, so zero or one. And classical computers [are] usually a transistor, [which is] like a circuit component that lets you store a zero or one value. Qubits are a bit different, but they still have that sort of zero-or-oneness. In classical bits, it’s one or the other; [with] qubits it’s any sort of combination, like a linear combination, in a sense.
But we think that these systems would make good qubits, and we are trying to characterize them. So we need to know a few things [about the qubits]. Namely, do they exhibit the behavior that a classical bit would exhibit? Do they have like a zero and one state that we can see and measure? Do they hold onto information for a long time? That's the hardest part about qubits:whether they can hold onto information for a long time. And so, we're investigating those properties. And that's been my thesis, just taking a sample, cooling it down to really, really cold temperatures, measuring these different things about it, and compiling a document that describes all these different characteristics of the sample. Then [I] make a claim about whether or not it would be a good candidate as a qubit.
When you work in high temperatures, [the] thermal fluctuations, etc., make the system a little more random [and] disoriented, [which] means stuff is more likely to lose its information. I guess in the simple[st] sense, when we work at cool temperatures, our system behaves like the theory says it should. But if we work at higher temperatures, then it's less aligned with the theory. The temperatures we get down to are 1.8 Kelvin, which is negative 200-something Celsius. I don't know the conversion to Fahrenheit, but [it’s] very cold.
The sample space that we're working with is a — about an inch in diameter and maybe like two inches tall — sort of cylindrical thing. And then even within that, the sample tube we use is very tiny. You need to work in a small space to keep things cool because the larger [the] space you need to cool, [it] takes a lot more energy.
Q: What motivated you to pursue this topic?
A: I think out of all the research at Amherst, the research that we're doing in this lab made the most sense to me. Every year in physics, the senior thesis students — at the end of the fall semester and at the end of the spring semester — present their work. And having heard all [of] the different talks out of the different labs, I thought, “Man, the research that's going on in [Professor Jonathan] Friedman[‘s] lab sounds the most interesting. it makes the most sense.”
I can see it [as] being sort of practical, but still in that lovely physics way, slightly impractical. I mean, we are investigating a system for a qubit, but we're not saying [that from] out of our lab, we can design a quantum computer. We're just saying this is a route [that] we think is viable and that needs more attention and more research. [For] the other labs, I can't say the same; they're very interesting, but not necessarily what I wanted to do.
Q: What previous research have you conducted during your time at Amherst?
A: I worked with Professor Jagu [short for Kannan Jagannathan] after my first year. That [research] wasn't experimental. — he's a theorist, and I did a lot of derivation of the mathematical theory behind classical mechanics. [It was] very much [a] “sit down and teach yourself” sort of summer experience, and that was great. It definitely prepared me for when I took advanced classical mechanics the following semester.
And then [in] sophomore fall, I worked for Professor [David] Hanneke. I did a lot of circuit design, fabrication work — or sending off stuff for fabrication, I suppose — and constructing devices for the lab. I constructed a box that basically splits voltage to a bunch of ports because we have tons of little devices that need maybe five volts, but, you know, [we] only have one five volt power supply, so [we] need[ed] to split that out about among a bunch of devices. So that that was sort of my “big thing.”
I worked for [ Hanneke] the following summer as well. But I did not have, unluckily, an appointment to get my eyes checked before I could work with the laser. So I spent a lot of time in that lab, not doing what I thought I was going to do. I don't think [it was] anyone's fault in that situation, but it just made for a summer experience that wasn't exactly what I wanted. You need an eye exam [because] it's sort of a legal proceedings thing, just to get a baseline for what your eyesight is like before you work in the lab. That way, you can't say, “Oh my vision is terrible, the laser hurt me,” and then sue the college for a lot of money. But that experience was not ideal. I actually turned down an REU for it because I thought that I was going to have a good project. But the REU wasn't what I wanted to do [either]. It was in graphene and materials science, which I wasn't excited about. But in hindsight, maybe that's what I should have done.
And that's basically everything leading up to my thesis.
Q: Who is your advisor and how have they helped you during this process?
A: My advisor is Professor Jonathan Friedman. He, this semester, sadly, has not been on campus for Covid reasons. But we meet virtually at least once a week, to discuss what I've done in my thesis, just to get a progress checkup. I tend to ask him a lot of questions. If there are any that are built up [and] that I haven't been able to answer myself by the time a meeting comes up, I'll ask him.
He's been very helpful in the whole process. He's [a] very fast [responder], responding on Slack to my messages. He does push me to learn some things, rather than just immediately giving the answer in certain instances. But many times, if I express my frustration about something, or I really just need the answer to get going on something else — I would say he is pretty good about gauging that, and he'll help me along in the right direction. He's great for suggesting papers that I should read, either to get an idea of things to talk about, what current research is going on or motivations for my thesis . He is great for [situations] where something has gone wrong in the lab; generally, he will know what to do to fix it, or have some advice on what to do.
Q: How have your ideas for your thesis changed over time?
A: I would say [that] in the beginning, I maybe didn't have a sense of the scope or timescale for things, or how much one hang-up on something can really eat away at a lot of time. Partly it's my fault, partly it's just [the nature of] experimental physics.
The part that's my fault was [that] I took on four classes last semester, instead of the three that we were offered because of Covid. This semester, I'm taking three classes. I decided I [was] just going to do that; that way, I have enough time to write, enough time to hang out with friends. But in terms of the scope of my thesis, I definitely think [that] in the beginning, I had a lot of ideas for, “Alright, I'm going to get this — I'm going to make sure I'm actually seeing what we expect to see as a baseline for this thing — and then I can actually go in depth on the characterization of our sample.” [I thought I would be able to clearly say] , “Here are these four or five things that I want to do.” But what ended up [happening] was, I spent a lot of time hung up last semester, not even being able to get the baseline measurement done. And that really delayed stuff. I came back over winter term and worked a lot by myself in the lab, just trying to knock out as much stuff as I could, and that sort of put me closer to back on track for things. But in the end — I got one of the bigger measurements done for sure — I really only got two of maybe the four or five things that I thought, “Oh hey, I'll be able to do this during my thesis.”
It really comes down to time. I mean as a thesis student, we spend the amount of time we would maybe spend on class, just with the lab. But realistically, that can only look like a part-time job, hours-wise: You might spend 20-ish hours a week in the lab. And that's normal. Or, you might not work much during the week; my lab has an equipment rotation, so I might not go in a couple days on the weekdays, but I might go in on the weekend and just shift the workload. It depends on what [is] available. But for sure, just [because of] the fact that it's not graduate school where research is your full-time job, the scope of projects changed and had to, in the sense that it got smaller as time went on.
Q: Has time been the biggest challenge for you when writing your thesis?
A: I think, sort of related to time, maybe time management. The biggest thing that I would say that I learned to do was [that] when the measurements were being taken for the thesis, I would work on something else for my thesis. So I would read a paper, or I would be writing a little bit — it depends on the semester — or I would be asking questions from the grad students who work in the lab from UMass. Really [I was] just learning to, not really “multitask,” but not to compartmentalize and say, “Oh, the measurements [are] being taken, so I need to sit here while the measurements [are] being taken.” As long as it's going smoothly, you can do other things, and that will really help stuff progress.
I'm looking forward to graduate school. In the first year, I'll still be taking classes. But in the second year onwards, it's just research and I'm looking forward to that
Q: Is this topic something you would like to continue after graduation?
A: I'm not necessarily continuing with molecular nanomagnets, but I'm doing almost identical techniques with the advisor that I will have for grad school. And that was my choice. I looked for a lot of programs that had very similar techniques or similar projects, because the halfway point was kind of when grad applications were due, and especially when I had to make a decision about grad school. The deeper I got into my thesis, the more I was kind of sad, and I said, “I wish I'd had another year or two to work on this because I feel like I could really dig deep and get a lot of good results out of it.”
Q: How has your experience been with finishing your thesis in the last several weeks?
A: That's the hardest part of the thesis. In a sense, you've got everything. You know you've got all your results, you have to analyze them, you have to argue for your results, or why they prove or say certain things about the system that you're working on.
Motivation is the hardest part at the end. Mostly because, if this were me needing to have something done by the end of the year but knowing that I would have more to come, like more years here at Amherst, I suppose maybe I wouldn't be as unmotivated. But because it's senior year, because I want to spend time with people, or [because] I'm exhausted and I just want to crash and not do anything — which is exacerbated by Covid — I think that this is the hardest part really for me. I have to force myself to sit down, put on some music, block off everything else, and say, “I'm going to write X amount of things,” or, “I'm going to knock out these figures that I need for my thesis,” or, “I'm going to edit this chapter.” And I just have to make myself do that, because otherwise I just won't do it. A month ago, I was like, “Oh, I have a month left,” and now I'm like, “I have twelve days, and I still have more than twelve pages to write.” And one page a day doesn't sound like a lot, but it really [is].
It's almost like the fear of starting it is the hardest part, like starting that one page and that one chapter. And [even] once I get into a flow, I'm like, “Man, that was a page I knocked out!” But getting started on a particular page or a particular figure is daunting.
Q: Do you have any advice for students who are debating writing a thesis, or who have just started their theses?
A: Yeah, [I have advice] at least for physics because I can't speak to English or theatre — they're all very different and [have] very different timelines. I would say for folks who've decided against grad school, unless you really want to do the thesis, and you're gung ho for that, and you've been that way since your first year, there's no reason to do it. It's a lot of extra work, and a lot of extra skills.
For folks who are on the fence about whether they want to do research in grad school, I think it's a good window into what that might be like. So I would definitely encourage that! And for folks who are trying to go to grad school, it's almost a must to do a thesis. So for those few categories, I would say that's the advice I would give for people who are first or second years here at Amherst.
I would say, maybe get an idea, try to work for a professor over the summer or during a semester — hopefully, a semester where you're not doubled up on physics classes because that is just asking for trouble. But, try to work at some point because that'll let you know if you click with the professor, or if that's sort of the research you maybe want to do for a thesis, or if it's not. It's a good way to get an idea of stuff, and to get paid to do it.
And then at the end, I would say [to] start writing over the Interterm. Trust me, get your introductory paragraph out of the way. And then, as much as you can write backwards, write backwards. That’s the advice my advisor gave me. Write as much of the results as you have, or, you know, section off the results you know you will have by the time you write everything up. And then you'll know what part of the experimental apparatus you’ll need to talk about, what techniques you need to talk about, what theory you need and what [your] motivation [is].