Tombez Lionel, Schilt Stéphane, Di Francesco Joab, Thomann Pierre, Hofstetter Daniel
Laboratoire Temps-Fréquence, Université de Neuchâtel, Avenue de Bellevaux 51, CH-2000 Neuchâtel, Switzerland.
Opt Express. 2012 Mar 26;20(7):6851-9. doi: 10.1364/OE.20.006851.
We report on the measurement of the frequency noise power spectral density in a distributed feedback quantum cascade laser over a wide temperature range, from 128 K to 303 K. As a function of the device temperature, we show that the frequency noise behavior is characterized by two different regimes separated by a steep transition at ≈200 K. While the frequency noise is nearly unchanged above 200 K, it drastically increases at lower temperature with an exponential dependence. We also show that this increase is entirely induced by current noise intrinsic to the device. In contrast to earlier publications, a single laser is used here in a wide temperature range allowing the direct assessment of the temperature dependence of the frequency noise.
我们报告了在128 K至303 K的宽温度范围内对分布反馈量子级联激光器中频率噪声功率谱密度的测量。作为器件温度的函数，我们表明频率噪声行为的特征是由在≈200 K处的陡峭转变分隔的两种不同状态。虽然频率噪声在200 K以上几乎不变，但在较低温度下它会急剧增加，呈指数依赖关系。我们还表明，这种增加完全是由器件固有的电流噪声引起的。与早期出版物不同，这里在宽温度范围内使用单个激光器，从而可以直接评估频率噪声的温度依赖性。
