论文标题
在激光阈值以下相干辐射的强耦合辅助形成
Strong-coupling-assisted formation of coherent radiation below the lasing threshold
论文作者
论文摘要
纳米级激光器的创建在连贯阈值之上运行是一个具有挑战性的问题。我们提出了一种使用系统在光和活动介质之间实现强耦合方案的系统来规避此问题的方法。在强耦合方面，能量振荡发生在腔和原子中的EM场之间。通过在泵送上应用适当的时间调制，可以控制这些能量振荡的方式，即激光系统中的连贯性出现在激光阈值以下。我们表明，在这种方法中，对于同一光子数，辐射线宽比常规激光器的线宽小两个数量级。另外，在系统达到正势倒置之前，输出辐射的二阶相干函数从两个降低到一个。我们的结果铺平了可以在激光阈值以下运行的连贯辐射的纳米级来源的道路。
The creation of nanoscale lasers that operate above a coherent threshold is a challenging problem. We propose a way to circumvent this issue using systems in which a strong coupling regime is achieved between the light and the active medium. In the strong coupling regime, energy oscillations take place between the EM field in the cavity and the atoms. By applying appropriate time modulation to the pumping, it is possible to control these energy oscillations in such a way that coherence in the laser system appears below the lasing threshold. We show that in this approach, the radiation linewidth is two orders of magnitude smaller than the linewidth of a conventional laser for the same photon number. In addition, the second order coherence function of the output radiation is reduced from two to one before the system reaches a positive population inversion. Our results pave the way for the creation of nanoscale sources of coherent radiation that can operate below the lasing threshold.
