Wen Pengyan, Tiwari Preksha, Scherrer Markus, Lörtscher Emanuel, Gotsmann Bernd, Moselund Kirsten E
IBM Research Europe-Zurich, Saeumerstrasse 4, CH-8803 Rueschlikon, Switzerland.
ACS Photonics. 2022 Apr 20;9(4):1338-1348. doi: 10.1021/acsphotonics.1c01951. Epub 2022 Mar 23.
There is a general trend of downscaling laser cavities, but with high integration and energy densities of nanocavity lasers, significant thermal issues affect their operation. The complexity of geometrical parameters and the various materials involved hinder the extraction of clear design guidelines and operation strategies. Here, we present a systematic thermal analysis of InP-on-Si micro- and nanocavity lasers based on steady-state and transient thermal simulations and experimental analysis. In particular, we investigate the use of metal cavities for improving the thermal properties of InP-on-Si micro- and nanocavity lasers. Heating of lasers is studied by using Raman thermometry and the results agree well with simulation results, both revealing a temperature reduction of hundreds of kelvins for the metal-clad cavity. Transient simulations are carried out to improve our understanding of the dynamic temperature variation under pulsed and continuous wave pumping conditions. The results show that the presence of a metal cladding not only increases the overall efficiency in heat dissipation but also causes a much faster temperature response. Together with optical experimental results under pulsed pumping, we conclude that a pulse width of 10 ns and a repetition rate of 100 kHz is the optimal pumping condition for a 2 μm wide square cavity.
激光腔有缩小尺寸的总体趋势，但对于纳米腔激光器的高集成度和能量密度而言，显著的热问题影响其运行。几何参数的复杂性以及所涉及的各种材料阻碍了清晰设计准则和运行策略的提取。在此，我们基于稳态和瞬态热模拟以及实验分析，对硅基磷化铟微腔和纳米腔激光器进行了系统的热分析。特别地，我们研究了使用金属腔来改善硅基磷化铟微腔和纳米腔激光器的热性能。通过拉曼测温法研究激光器的发热情况，结果与模拟结果吻合良好，二者均表明包覆金属的腔体能使温度降低数百开尔文。进行瞬态模拟以增进我们对脉冲和连续波泵浦条件下动态温度变化的理解。结果表明，金属包覆不仅提高了整体散热效率，还导致更快的温度响应。结合脉冲泵浦下的光学实验结果，我们得出结论，对于一个2μm宽的方形腔，10ns的脉冲宽度和100kHz的重复频率是最佳泵浦条件。
