Semiconductor disk laser at 2.05 μm wavelength with <100 kHz linewidth at 1 W output power

Abstract

We report on an optically pumped single-mode GaSb-based semiconductor disk laser (SDL) emitting at 2.05 μm at an output power of 960 mW (1100 mW) with a side-mode suppression of better than 30 dB (20 dB). A linewidth of 60 kHz (sampling time: 100 μs) was measured at an output power of 960 mW. This improvement in output power over previous reports, which was achieved via a careful design of the SDL cavity paying close attention to the spatial overlap between cavity mode and pump spot, makes this class of SDL particularly attractive for remote sensing and optical free-space communication.

Frequency stabilization of an ultraviolet semiconductor disk laser

“…Figure 4 shows the fundamental laser linewidth measured over different time scales ranging from 10 μs to 10 s. The laser linewidth remains between 25 and 30 kHz over long sampling times and steeply decreases below 10 ms to reach a value of 8 kHz at 10 μs. This decrease of the linewidth when measured on short timescales is to be expected with noise dominated by low frequencies [17]. Moreover, the fact that the linewidth peaks around 10 ms and remains nearly constant over longer timescales confirms, as observed with the PSD, the majority of the frequency noise is contained within a 1 kHz bandwidth.…”

Widely Tunable High-Power Two-Color VECSELs for New Wavelength Generation

“…High power near infrared operation has been demonstrated [4]. The open cavity design of a VECSEL provides excellent access to the high intracavity circulating power which allows for linewidth control, wavelength tuning and efficient intracavity nonlinear frequency conversion [5]- [7]. Semiconductor lasers providing high beam quality, high power, and wide tunability at two different wavelengths are of great interest for new color generation by nonlinear conversion via sum and difference frequency generation [8], [9].…”

Optically pumped VECSELs: review of technology and progress

“…In practice, the VECSEL linewidth is typically determined using heterodyne measurements with two similar lasers [266,279,280] or from the frequency noise spectral density via calculation [227,259,281,282]. In any case, the linewidth increases with the sampling time as more noise sources are taken into account [266,268,280,283].…”

“…Nevertheless, such measurements with delay lines shorter than the laser coherence length have been used for determining a lower limit for the coherence length [275][276][277], which can then provide a rough estimate for the upper limit of the laser linewidth [278]. In practice, the VECSEL linewidth is typically determined using heterodyne measurements with two similar lasers [266,279,280] or from the frequency noise spectral density via calculation [227,259,281,282]. In any case, the linewidth increases with the sampling time as more noise sources are taken into account [266,268,280,283].…”