Feb 6 (Thu) @ 10:00am: "Direct-bonding-based Epitaxial Layer Transfer for High-performance Photonics," Garrett Cole, Thorlabs Crystalline Solutions

Location: Engineering Science Building (ESB), Room 2001

Abstract

In this presentation, I provide an overview of advanced optical solutions employing direct-bonded III-V heterostructures. The core focus will be on a groundbreaking new concept in optical interference coatings, leveraging a unique combination of semiconductor materials and microfabrication techniques together with super-polished bulk optics. These substrate-transferred crystalline coatings, or “semiconductor supermirrors,” were first demonstrated in 2013 and now achieve excess optical losses below 3 parts per million (ppm) for near-IR wavelengths, enabling laser reference cavities with finesse > 500,000 (corresponding to an optical quality factor, Q, of ~250 billion). In addition to low optical losses, the near-structural perfection of these epitaxial mirrors significantly reduces coating Brownian noise, a crucial advancement in precision measurement systems such as optical atomic clocks and gravitational wave detectors. Recent achievements include the production of low-noise mirrors up to 20 cm in diameter and the development mid-IR reflectors capable of a finesse exceeding 400,000 at 4.5 µm, promising significant improvements in spectrometers for trace gas detection. Leveraging our bonding-based manufacturing expertise, I will additionally introduce efforts in heterogeneously integrated active and passive photonic systems. Looking ahead, I see a bright future for compound-semiconductor-on-insulator devices for applications requiring the ultimate levels of optomechanical performance.

Bio

Garrett D. Cole obtained his Ph.D. from UCSB in 2005 and subsequently held positions including the first employee of Aerius Photonics LLC (now FLIR Electro-Optics), a postdoc at LLNL, a Marie Curie Fellow of the Austrian Academy of Sciences Institut für Quantenoptik und Quanteninformation (headed by Anton  Zeilinger, Physics Nobel Laureate 2022), and a university assistant at Universität Wien Fakultät für Physik. In 2012, Dr. Cole, together with Prof. Markus Aspelmeyer, founded Crystalline Mirror Solutions (CMS), a quantum optomechanics spin-off commercializing semiconductor supermirrors for laser-based metrology and manufacturing. CMS was successfully acquired by Thorlabs in Dec. 2019 and rebranded as Thorlabs Crystalline Solutions. In addition to numerous startup prizes, Dr. Cole received the LIGHT2015 Young Photonics Entrepreneur Award, a Berthold Leibinger Innovationspreis (2016), an SPIE Prism Award (2017), and served as a Unesco Trust Science Champion (International Day of Light, 2021). For 2024, he was selected as a member of the Photonics100 and elected Fellow of Optica.

Hosted by: ECE Department