Highly efficient generation of coherent light at 2128 nm via degenerate optical-parametric oscillation

Christian Darsow-Fromm*, Maik Schroeder, Julian Gurs, Roman Schnabel, Sebastian Steinlechner

*Corresponding author for this work

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2 Citations (Web of Science)


Cryogenic operation, in conjunction with new test-mass materials, promises to reduce the sensitivity limitations from thermal noise in gravitational-wave detectors. Currently, the most advanced materials under discussion are crystalline silicon as a substrate with amorphous silicon-based coatings. However, they require operational wavelengths around 2 mu m to avoid laser absorption. Here we present a light source at 2128 nm based on a degenerate optical parametric oscillator to convert light from a 1064 nm nonplanar ring-oscillator. We achieve an external conversion efficiency of (87.1 +/- 0.4)% at a pump power of 52 mW in periodically poled potassium titanyl phosphate (internal efficiency was 93%). With our approach, light from the established and existing laser sources can be efficiently converted to the 2 mu m regime while retaining the excellent stability properties. (C) 2020 Optical Society of America

Original languageEnglish
Pages (from-to)6194-6197
Number of pages4
JournalOptics Letters
Issue number22
Publication statusPublished - 15 Nov 2020

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