Kaneda Yushi, Hart Michael, Warner Stephen H, Penttinen Jussi-Pekka, Guina Mircea
Opt Express. 2019 Sep 16;27(19):27267-27272. doi: 10.1364/OE.27.027267.
A vertical external-cavity surface-emitting laser (VECSEL) with a twisted-mode configuration is demonstrated. This architecture is particularly advantageous for power scaling of single-frequency VECSELs employing multiple gain mirrors in folded cavities. In such a configuration, some of the gain mirrors are inherently at the fold, and the lasing spectrum becomes unstable. This is caused by four waves interfering, destabilizing the standing wave pattern at the quantum wells. We show that the lasing spectrum can be narrowed by employing a twisted-mode configuration, which stabilizes the standing-wave pattern at the gain mirror. Furthermore, single-frequency output of more than 10 W at 1178 nm is demonstrated for a VECSEL employing two gain mirrors in a standing-wave cavity. In comparison, the output power for operation with one gain mirror only was 7.4 W when operating in single frequency. The choice of wavelength for the work reported in this paper is motivated by the opportunity to demonstrate compact VECSEL-based guide star lasers for adaptive optics via frequency doubling to the sodium D resonance at 589 nm.
展示了一种具有扭曲模式配置的垂直外腔面发射激光器（VECSEL）。这种架构对于在折叠腔中采用多个增益镜的单频VECSEL的功率扩展特别有利。在这种配置中，一些增益镜固有地处于折叠处，并且激光光谱变得不稳定。这是由四波干涉引起的，它破坏了量子阱处的驻波模式。我们表明，通过采用扭曲模式配置可以使激光光谱变窄，这会使增益镜处的驻波模式稳定。此外，对于在驻波腔中采用两个增益镜的VECSEL，在1178nm处展示了超过10W的单频输出。相比之下，仅使用一个增益镜进行单频操作时的输出功率为7.4W。本文报道的工作中波长的选择是受通过倍频到589nm的钠D共振来展示基于VECSEL的紧凑型导星激光器用于自适应光学的机会所驱动。
