In this paper, the unconventional cryogenic cooling process is introduced as a potential method to overcome the inherent thermal limitations in high power fiber lasers.It is shown that the signal power and efficiency of the desired laser line linearly decreases at cryogenic bath temperatures, mainly due to the reduction of pump absorption of the fiber core, thermally depopulated inversion of levels at four-level transition energy structure and the spectral distribution of energy which takes place due to the multiple-line oscillations at LNT. Particularly, the multiple-line oscillation at LNT indicates that the low temperature is more suitable for the emission of short wavelength, which has more optical gain. However, lucidly low phononic energies at cryo-temperatures notably narrow the linewidth while the discrete Stark sublevels' populations start depleting to reduce the efficiency.

中文翻译：

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温度对掺镱石英光纤激光器性能的影响


本文介绍了非常规低温冷却过程作为克服高功率光纤激光器固有热限制的潜在方法。结果表明，所需激光线的信号功率和效率在低温浴温度下线性下降，这主要是由于纤芯泵浦吸收的减少、四能级跃迁能级结构中能级的热稀疏反转以及由于 LNT 处的多线振荡而发生的能量谱分布。特别是LNT处的多线振荡表明低温更适合短波长的发射，具有更高的光学增益。然而，低温下的明显低声子能量显着缩小了线宽，而离散斯塔克亚能级的布居开始耗尽，从而降低了效率。