High power single-frequency continuously-tunable compact extended-cavity semiconductor laser

Opt Express. 2009 Jun 8;17(12):9503-8. doi: 10.1364/oe.17.009503.

Abstract

We demonstrate high power high efficiency (0:3 W) low noise single frequency operation of a compact extended-cavity surface-emitting-semiconductor-laser exhibiting a continuous tunability over 0:84 THz with high beam quality. We took advantage of thermal lens-based stability to develop a short (< 3 mm) plano-plano external cavity without any intracavity filter. The structure is optically pumped by a 1 W commercial 830 nm multimode diode laser. No heat management was required. We measured a low divergence circular TEM(00) beam at the diffraction limit (M(2) < 1:05) with a linear light polarization (> 37 dB). The side mode suppression ratio is 60 dB. The free running laser linewidth is 850 kHz limited by pump induced thermal fluctuations. Thanks to this high-Q external cavity approach, the frequency noise is low and the dynamics is in the relaxation-oscillation-free regime, exhibiting a low intensity noise, with a cutoff frequency approximately 250 MHz above which the shot noise level is reached. We show that pump properties define the cavity design and laser coherence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Computer-Aided Design
  • Equipment Design
  • Equipment Failure Analysis
  • Lasers, Semiconductor*
  • Reproducibility of Results
  • Sensitivity and Specificity