The industry’s most innovative people 2024 Garrett Cole


Organisation: Thorlabs Role: Manager, Thorlabs Crystalline Solutions Based in: Santa Barbara, CA, US Education: PhD


We know Photonics100 honorees keep exalted company, but how many have hobnobbed with the likes of Jeff Bezos, Stephen Wolfram and even Luke Skywalker himself? In the course of his work for Thorlabs Crystalline Solutions, Garrett Cole can lay claim to all three.


What are you currently working on? What will the impact be? I continue spearheading basic research as well as commercial development of "semiconductor supermirrors", based on substrate-transferred single-crystal GaAs/ AlGaAs optical interference coatings. Improving the sensitivity of optical


precision measurement systems has a far- reaching impact, from fundamental scientific research efforts to advanced technologies including trace chemical analysis, inertial navigation, and broadband communications. Crystalline coatings have now redefined the performance metrics of ultrastable resonators for cavity-stabilised laser systems, enabling the world's lowest-noise lasers for precision spectroscopy, optical atomic clocks, and neutral atom quantum computing systems.


What’s your biggest research priority in the coming year? There are two parallel paths that my group is pursuing: 1) The development of extremely high reflectivity mid-infrared mirrors for trace gas detection and laser- based manufacturing, and 2) Scaling up the maximum achievable diameter of our coatings (aiming for >300mm), making these mirrors amenable to laser- interferometer-based gravitational-wave detectors. In the mid-IR domain, in early 2023 we demonstrated the highest finesse ever achieved in this spectral range, constructing a linear cavity with a finesse >400,000 (corresponding to a mirror reflectance >99.999%) at a centre wavelength of 4,500nm. This was enabled by an improved manufacturing process that allowed us to achieve the lowest optical scatter plus absorption ever measured at these wavelengths (by nearly an order of magnitude compared to competing PVD processes). This marks an important milestone in optical coating development, whereby mid-infrared mirrors can now reach comparable levels of optical losses, as was realised in visible and near-infrared coatings in the mid-1970s. In terms of scaling the maximum mirror


diameter, while current gravitational-wave detector mirrors are ~35cm in diameter. We are actively pursuing collaborative projects in order to reliably produce such large mirrors – the good news is that this is an engineering challenge and there are no fundamental physical limitations.


"Improving the sensitivity of optical precision measurement systems has a far- reaching impact"


size, the aims are more scientifically focused. Building upon more than a century of progress, state-of-the-art Fabry-Perot cavities have reached a point where their ultimate performance is limited by fundamental thermo-mechanical fluctuations, or Brownian motion, of the mirrors themselves. These unavoidable fluctuations now stand as a barrier to ever more precise measurements of time and space, such as those obtained using advanced optical atomic clocks and interferometric gravitational wave detectors. A breakthrough in this area requires


the development of mirrors, or, more specifically, coating materials, that also exhibit high mechanical quality. Based on statistical mechanics, most notably the fluctuation dissipation theorem, one finds that enhanced stability, realised through a reduction in the Brownian noise, is obtained by minimising the intrinsic elastic loss (think "internal friction") of the mirror coatings. This is a major impediment to improving laser-based gravitational-wave observatories. The largest mirrors that we can currently fabricate are ~20cm in


What is your proudest moment in photonics so far? I am going to cheat here and list a few... Transitioning from basic research in order to build up a high-technology hardware start- up was extremely challenging, so it was fantastic to receive acknowledgement via various accolades, such as the LIGHT2015 Young Photonics Entrepreneur Award, a Berthold Leibinger Innovationspreis in 2016, and an SPIE / Photonics Media Prism Award for new Materials and Coatings in 2017. Most recently I was chosen as a "Trust Science Champion" as part of the UNESCO International Day of Light on May 16, 2021. I dedicated the latter to my father, an unwavering supporter, who had unfortunately passed away just 10 days before that was conferred. Two more notable and very unique


life experiences occurred in 2018 and 2019 when I was hosted by Jeff Bezos at the invitation-only MARS (machine learning, automation, robotics, and space) Conferences held in Palm Springs, CA, to discuss our work on the development of mirrors for future gravitational wave detectors (with Barry Barish and Dave Reitze of LIGO). During these multi-day events, I was able to hobnob with technical luminaries such as Nathan Myhrvold (Microsoft's first CTO and a James Beard culinary award winner), Stephen Wolfram of Mathematica fame, plus titans of industry including then CEO of Intel, CTO of Ford and so on... There were also celebrity attendees such as Mark Hamill (Luke Skywalker!), Ron Howard (one of my favourite directors), and Adam Savage, formerly of Mythbusters.


Where can people see you in person over the next year? I reliably attend Photonics West and CLEO. I also highly encourage folks to stop by and check out our office and lab space at Thorlabs Crystalline Solutions in sunny Santa Barbara, California. Following fun technical discussions, it is less than 10 minutes to walk to the beach from our location!


2024 Photonics100 27


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56