Early-career Q&A: Gar-Wing Truong on joining a startup

Editor’s note: This is the first in a series of Q&As with early-career researchers, with a focus on careers in industry, contributed by Physics Today‘s partners at the American Institute of Physics Career Network.

In 2016 Gar-Wing Truong was enjoying his final year as a postdoctoral researcher in precision spectroscopy at NIST in Boulder, Colorado, and envisioning a future in academia. But his plans changed when he saw an advertisement for a lead scientist position at Crystalline Mirror Solutions (CMS), a startup developing ways to precisely characterize the tiny optical losses of mirror coatings. Today Truong continues at the company, which has since been acquired by Thorlabs. He develops crystalline mirror coatings for scientific applications in Santa Barbara, California.

Physics Today recently talked to Truong about his career path in physics, his work at NIST, and his thoughts on the perils and prospects of joining a startup. The conversation revealed a few recurring themes: mentors who helped shape his outlook, hands-on involvement in projects at every step of his adult life, and risk-taking as an expression of his passion for the work.

PT: How did you become interested in physics?

TRUONG: I had a very passionate and, fortunately for me, patient physics teacher in high school. I grew up in Australia with parents who had emigrated from Vietnam. English and the humanities were a little more difficult for me, whereas the quantitative sciences seemed easier. They might not actually have been easier, but there were tests, methodology, right and wrong answers. From there, my physics teacher came to mentor me, and through his passion I discovered physics and chemistry.

I scored the highest on the physics SAT equivalent in my cohort that year, so that was a huge boost of confidence. Clearly I understood something! That led me to pursue a combined science and engineering degree at the University of Western Australia [UWA].

PT: What did you study for your PhD and postdoc?

TRUONG: I did my PhD at UWA in atomic and molecular physics. The focus of my research was the precision spectroscopy of atomic vapors for primary thermometry. Led by the ongoing push to define all SI base units in terms of fundamental constants instead of with reference to physical artifacts, there was an international effort to determine the Boltzmann constant with smaller total uncertainty than was known at the time. Although our method departed greatly from the leading and more established methods of the time, I’m proud to have contributed to a topical body of work that eventually achieved its goal in 2019, when the kelvin was redefined in terms of the Boltzmann constant.

I spent time at both NIST campuses. The first time was in Gaithersburg, Maryland, working with Joe Hodges’s group doing cavity ring-down spectroscopy for precision spectroscopy of greenhouse gases, mostly carbon dioxide and water vapor. After returning to Australia to complete my PhD, I took a postdoc position with Nate Newbury’s group at NIST in Boulder. There I joined a team that pioneered the method of coherent dual-comb spectroscopy. I built a transportable version from the ground up and used it to measure CO₂, this time in open air over kilometer-scale path lengths.

It’s cool to know that since I left NIST, that system has been used to monitor, quantify, and attribute greenhouse gas fluxes over the city of Boulder, and similar systems are now commercialized for well-pad monitoring.

PT: What motivated you to go directly from a postdoc to a startup?

TRUONG: Prior to the end of my postdoc, I saw an advertisement for what seemed like an ideal position for my background, and I joined CMS. It was definitely an adventure. I’m not business savvy now and was even less so then. Looking back, some of the risks went over my head, but the excitement was so much—I mean this was, roughly speaking, a dream job. The technical fit and the clear opportunities in the role made it so enticing. You hear some things about working at a startup, but the full implications didn’t hit me at the time. There was almost no hesitation.

I had one short conversation back then with Garrett Cole, the cofounder and chief technology officer of CMS, about the general uncertainty with small businesses. He didn’t sugarcoat it, but in projecting a lot of experience, he made me feel secure that someone was handling the business side of things, so I could handle my technical side of things. No matter what happened, I knew I would gain valuable and hands-on experience.

Looking back now, maybe I should’ve been a little more hesitant to join up. What’s funny is that I was sent moving in this direction by my postdoc adviser. Prior to talking to him, I was pretty set on an academic career. And he had a very successful career in academia. Yet I was becoming more aware of the challenges beyond the technical work, such as how grants get off the ground, and I wondered whether a career in academia was something I still wanted to pursue. I didn’t know what industry would be like, but he encouraged me to try it out if I was even a little bit interested. He told me to be bold.

PT: That sounds like advice that would make a large impact on someone.

TRUONG: Yes. And through his guidance I just dove in. I would overwhelmingly suggest that if you have the opportunity to join a startup and you’re at a flexible enough place in your life to pursue slightly higher risk, definitely do it. Working with a small team, the agility of the environment is unparalleled.

I worked directly with experts in distinct fields; our expertise didn’t overlap. In that way, there was pressure to get your own stuff right from day one. It was a little daunting, but I got to see the immediate effects from my efforts, whereas as part of a larger team, the immediacy might not have been there. The nature of working at a startup is that you’re so focused on one problem; you get to dive in deep for a particular result, which I think connects with the mindset of a PhD or postdoc.

PT: What are some of the things you’re working on now?

TRUONG: The CMS role was created with the goal of characterizing the optical losses of mirror coatings with on the order of 10 ppm of loss. It turns out that cavity ring-down is a method well suited for this sort of measurement. End users were typically using CMS mirrors to make stable reference cavities with lower noise floors, and so my experience in laser stabilization was also extremely relevant.

The manufacturing and processing of crystalline coatings are fundamentally different from other high-performance coatings offered out there. The coatings are particularly used for certain niche applications where fundamental noise plays a part. This type of coating fabrication technology has been used to help measure quantum backaction cancellation in the audio band, room-temperature optomechanical squeezing, and even precision gravitational-wave astronomy measurements.

As part of CMS, we’re able to offer these coatings at the discrete component level, and we’ve started to branch out to build up optical cavities and optical resonators composed of these mirrors.

With the backing of Thorlabs, we’re beginning to push this technology up the application chain. We’re working on building a more integrated laser system to ultimately demonstrate performance. Just like with any metrology project, the devil’s always in the details.

PT: A lot of practices in your field are entrenched. How do you push past the inertia of doing things as they’ve always been done?

TRUONG: For me it means the need to do demonstrations, the need to be convincing. If a field is already in the tradition of doing it one way, the benefits have to outweigh the costs. For us, that means building up a demonstration system that will tease out the advantages of our products. It entails building high-quality, high-spectral-purity lasers to join in the movement internationally of more accurate measurements.

PT: In that way, it sounds like a continuation of your work when you joined the startup: a team striving toward a similar goal.

TRUONG: Yeah, I think that’s right. Part of the work is to demonstrate performance, but more personally, it’s also just the path to what I find so technically interesting. As someone who’s interested in taking on that challenge, I’m motivated by it.

PT: What does a typical day look like for you?

TRUONG: If we’re talking pre-COVID, my schedule consisted of about 50% working in the lab, since my expertise is so technical. Even when I’m in the lab, sometimes I’ll be doing design work or checking something on the computer. There’s some amount of my time dealing with shipping, inventory, and general lab facility duties, a holdover from us being a startup. I don’t travel or do sales, so I’m somewhat insulated from the customer, but if there is a specific technical question, then it will usually come to me.

PT: What’s your favorite part of the job? What are you looking forward to in your position?

TRUONG: I’m very lucky. All the technical work I’m involved in is what motivates me. And I really have my background to thank for that. All the technical experience from my PhD and postdoc comes into play almost every day.

As for what I’m looking forward to, I want to stay technical. That’s kind of the dream, right? Staying in the lab to be involved in interesting, challenging topics. As a larger company, Thorlabs has provided great opportunities to branch out into more fields and projects and learn from more experienced staff. So I’m continuing to gain experience, continuing to have fun, continuing to learn new stuff, and continuing to contribute in a meaningful way. In short, I’m interested in a research and development career in an industrial setting.

PT: What advice would you give to undergraduate and graduate students who are interested in following a similar career path?

TRUONG: Try things out. Try to be outstanding in your field and to contribute your specialties. You’ll get noticed, and then you’ll be able to get experience under your belt. It’s hard to know what skills you’ll need, but a variety of experience definitely helps. I still go back to things I learned from my PhD and postdoc.

Also reach out to your colleagues and the people you know. Keep in touch, build a network. Having the curiosity to ask about their experiences is just as important as finding mentors who you can learn from.

No one has a crystal ball, so apply yourself where you can. Work hard in your field, and don’t be afraid of challenges. Going off the beaten path has worked well for me.