This study investigates the thermal performance of cryogenic micro-pin fin coolers for high-power laser diode (LD) bars. An open-loop liquid nitrogen cooling system, used to operate LD bars at cryogenic temperatures, is developed and characterized. The comparison study demonstrates that the total thermal resistance value of the micro-pin fin cooler, ranging from 0.03 to 0.04 °C/W, is only 1/3 of that of the micro-gap cooler and, thus, contributes significantly to reducing the LD operating temperature and enhancing its efficiency. In this study, the peak optical power of 68.8 W was observed at an LD bar package base temperature of − 100 °C, providing a 20% increase relative to the optical power of 57.3 W for a nominal operating condition with an LD bar package base temperature of 41 °C. This result clearly illustrates the enhancement in optical performance made possible by cryogenic cooling with a pin fin microcooler.

这项研究调查了用于大功率激光二极管（LD）棒的低温微针鳍式冷却器的热性能。开发并表征了用于在低温下操作LD棒的开环液氮冷却系统。对比研究表明，微针翅片冷却器的总热阻值在0.03至0.04°C / W的范围内，仅为微间隙冷却器的总热阻值的1/3，因此，在很大程度上降低了LD的工作温度提高了它的效率。在这项研究中，在LD bar封装基座温度为-100°C时观察到了68.8 W的峰值光功率，相对于LD bar封装基座的标称工作条件下的57.3 W的光功率，提供了20％的增加。温度为41°C。