Flood Andrew G, Kherani Nazir P
Opt Lett. 2021 Jun 15;46(12):2916-2919. doi: 10.1364/OL.427104.
Solar-pumped lasers and optical amplifiers continue to draw research interest with advances in nanomaterials science and technology. Establishing accurate detailed balance limits for inversion in these systems is essential. In this Letter, we re-examine the threshold limits for inversion in broadband-pumped lasers, with reference to those provided by Roxlo and Yablonvitch [Opt. Lett.8, 271 (1983)OPLEDP0146-959210.1364/OL.8.000271], where they determined the minimum Stokes shift and the minimum ratio of pump band to emission band absorption constants-based on independent consideration of the emission at pump and emission frequencies. In contrast, the derivation here simultaneously accounts for emission in both the pump and emission bands, which in turn leads to a single consolidated inequality that serves to establish the revised threshold requirements for inversion. Upon applying this new unified relationship to solar-pumped devices, a large increase in the minimum required Stokes shifts for 1-sun devices, particularly at larger pump energies and smaller ratios of /, is found. The maximum possible efficiencies of solar-pumped devices are calculated using this new relation.
随着纳米材料科学与技术的进步，太阳能泵浦激光器和光放大器持续吸引着研究兴趣。为这些系统中的粒子数反转建立精确的详细平衡极限至关重要。在本信函中，我们参考Roxlo和Yablonvitch [《光学快报》8, 271 (1983年)，OPLEDP0146 - 959210.1364/OL.8.000271]所给出的结果，重新审视宽带泵浦激光器中粒子数反转的阈值极限，他们基于对泵浦频率和发射频率处发射的独立考虑，确定了最小斯托克斯频移以及泵浦带与发射带吸收常数的最小比值。相比之下，此处的推导同时考虑了泵浦带和发射带中的发射，这进而导致一个单一的综合不等式，用于确定修正后的粒子数反转阈值要求。将这一新的统一关系应用于太阳能泵浦器件时，发现对于1个太阳光照强度的器件，所需的最小斯托克斯频移大幅增加，特别是在泵浦能量较大且/比值较小时。利用这一新关系计算了太阳能泵浦器件的最大可能效率。
