Anne Tropper: The 2021 SPIE Maiman Laser Award
Anne Tropper has worked in optical physics for more than 40 years — often ahead of her time — influencing the work of many groups in fields that include fiber lasers and amplifiers; upconversion lasers; spin dynamics in semiconductors; and ultrafast semiconductor laser physics. Tropper's doctoral research at the University of Oxford, where she was taught by Nina Byers, involved low-temperature structural phase transitions in rare-earth oxide crystals, an unfashionable topic but one which necessitated the rigorous study of the electronic structure and interactions of rare-earth ions that was later on so useful to her in her fiber laser research. A brief postdoctoral spell at Oxford's Clarendon Laboratory led to a Lindemann Fellowship, held in conjunction with a Visiting Scientist position at the IBM San José Research Laboratory (now Almaden). Rare-earth spectroscopy at IBM San Jose at that time, led by such luminaries as Roger Macfarlane, Robert Shelby and Mark Levinson, was rich in compelling phenomena, including optical coherent transients; slow optical dephasing; huge ratios of inhomogeneous to homogeneous optical broadening; the promise of optical hole-burning data storage, and optical computing.
Over her career, both as a consulting engineer and an academic — she was a founding member of the Optoelectronics Research Centre at Southampton as well as head of its Quantum Light and Matter research group between 2007 and 2012 — Tropper made many pioneering contributions to solid-state, fiber, and semiconductor laser science and technology. When she joined the University of Southampton in 1983, for example, she developed an interest in laser physics. She was the first to demonstrate the ytterbium silica fiber laser and highlight the unique potential of this system for efficient high-power operation, exploited today in industrial lasers. New fiber lasers first reported by her group include thulium and holmium silica in the mid-infrared, and infrared-pumped visible lasers based on praseodymium-doped fluoride glass. In 2000 she worked with ETH Zurich's Ursula Keller on the first passively mode-locked Vertical External-Cavity Surface-Emitting Laser (VECSEL). Since 1991, Tropper has published more than 60 conference proceedings with SPIE; she also chaired the SPIE LASE conference on VECSELS at Photonics West in 2012.
"Tropper's career has been characterized by original ideas, a willingness to take risks, openness to the research community, and taking huge pleasure in successful, win-win collaborations," says Keller. "She moved several times into new fields where she had no track record and was able to make an impact with her publications and influence the direction of research in other groups. She is also a generous teacher and mentor: Anne always believed that the students and postdocs she trained were the most important output of all from her research group's work."