Ultrastable lasers

Investigations of crystalline mirrors and closed cycle cooling at 124 K

authored by: C. Y. Ma, J. Yu, T. Legero, S. Herbers, D. Nicolodi, M. Kempkes, F. Riehle, D. Kedar, J. M. Robinson, J. Ye, U. Sterr
Abstract: We have investigated crystalline AlGaAs/GaAs optical coatings with three ultra-stable cavities operating at 4 K, 16 K, 124 K and 297 K. The response of the cavities' resonance frequencies to variations in optical power indicates non-thermal effects beyond the photo-thermo-optic effect observed in dielectric coatings. These effects are strongly dependent on the intensity of the intracavity light at 1.5 μm. When the rear side of the mirrors is illuminated with external light, we observe a prominent photo-modified birefringence for photon energies above the GaAs bandgap, which points to a possible mechanism relating our observations to the semiconductor properties of the coatings. Separately, we also present a low maintenance evolution of our 124 K silicon cavity system where the liquid nitrogen based cooling system is replaced with closed cycle cooling from a pulse-tube cryo-cooler.
External Organisation(s): Physikalisch-Technische Bundesanstalt PTB
JILA
Type: Conference article
Journal: Journal of Physics: Conference Series
Volume: 2889
ISSN: 1742-6588
Publication date: 2024
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Physics and Astronomy
Electronic version(s): https://doi.org/10.1088/1742-6596/2889/1/012055 (Access: Open)

BibTeX

@article{3f9128abcde34682884a65698a58d9f3,
title = "Ultrastable lasers: Investigations of crystalline mirrors and closed cycle cooling at 124 K",
abstract = "We have investigated crystalline AlGaAs/GaAs optical coatings with three ultra-stable cavities operating at 4 K, 16 K, 124 K and 297 K. The response of the cavities' resonance frequencies to variations in optical power indicates non-thermal effects beyond the photo-thermo-optic effect observed in dielectric coatings. These effects are strongly dependent on the intensity of the intracavity light at 1.5 μm. When the rear side of the mirrors is illuminated with external light, we observe a prominent photo-modified birefringence for photon energies above the GaAs bandgap, which points to a possible mechanism relating our observations to the semiconductor properties of the coatings. Separately, we also present a low maintenance evolution of our 124 K silicon cavity system where the liquid nitrogen based cooling system is replaced with closed cycle cooling from a pulse-tube cryo-cooler.",
author = "Ma, {C. Y.} and J. Yu and T. Legero and S. Herbers and D. Nicolodi and M. Kempkes and F. Riehle and D. Kedar and Robinson, {J. M.} and J. Ye and U. Sterr",
note = "Publisher Copyright: {\textcopyright} Published under licence by IOP Publishing Ltd.; 9th Symposium on Frequency Standards and Metrology, FSM 2023 ; Conference date: 16-10-2023 Through 20-10-2023",
year = "2024",
doi = "10.1088/1742-6596/2889/1/012055",
language = "English",
volume = "2889",
journal = "Journal of Physics: Conference Series",
issn = "1742-6588",
publisher = "IOP Publishing Ltd.",
number = "1",
}