778.1 nm distributed feedback lasers for Rb two-photon atomic systems with sub-4 kHz linewidths

E. Di Gaetano, B. Keliehor, K. Gallacher, P.F. Griffin, M. Sorel, E. Riis, D.J. Paul

Research output: Contribution to journalArticlepeer-review

3 Downloads (Pure)

Abstract

A new epitaxial layer design with a double mode expander layer, high refractive index claddings, and an aluminum-free active area has been used to demonstrate distributed feedback lasers operating at 778.1 nm wavelength with reduced Lorentzian linewidth aimed at miniature atomic clock applications. The design also reduces the vertical beam divergence to improve the modal matching with optical fibers as well as maintain the high power output and reduce the emission linewidth. The lasers demonstrate single-mode operation with an over 35 dB side-mode suppression ratio, a power output ≤58 mW, a coupling efficiency to tapered fibers ≤40%, and a Lorentzian linewidth of 3.7 kHz. The performance allowed the free-running distributed feedback lasers to demonstrate spectroscopy of Rb vapor, which resolved the 85Rb and 87Rb two-photon transitions.
Original languageEnglish
Article number056114
Number of pages13
JournalAPL Photonics
Volume9
Issue number5
DOIs
Publication statusPublished - 30 May 2024

Keywords

  • semiconductor heterostructures
  • waveguides
  • two photon fluorescence light microscopy
  • epitaxy
  • spectroscopy
  • spectral linewidths
  • quantum wells
  • semiconductor lasers
  • rubidium

Fingerprint

Dive into the research topics of '778.1 nm distributed feedback lasers for Rb two-photon atomic systems with sub-4 kHz linewidths'. Together they form a unique fingerprint.

Cite this