Ultrastable lasers

Investigations of crystalline mirrors and closed cycle cooling at 124 K

verfasst von
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.

Externe Organisation(en)
Physikalisch-Technische Bundesanstalt (PTB)
Joint Institute for Laboratory Astrophysics (JILA)
Typ
Konferenzaufsatz in Fachzeitschrift
Journal
Journal of Physics: Conference Series
Band
2889
ISSN
1742-6588
Publikationsdatum
2024
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Allgemeine Physik und Astronomie
Elektronische Version(en)
https://doi.org/10.1088/1742-6596/2889/1/012055 (Zugang: Offen)