论文标题
非线性引起的异常单模激光和非铁皮效应
Anomalous single-mode lasing induced by nonlinearity and the non-Hermitian skin effect
论文作者
论文摘要
单模操作是在高泵功率上运行的激光器的理想但难以捉摸的属性。通常，单模激光可以接近阈值，但是由于模式间增益竞争，增加泵功率会导致多个激光峰。我们提出了一个相反行为的激光器：多模式激光发生在低输出功率下，但是泵送超过一定值会产生单个激光模式，所有其他候选模式都具有负有效增益。这种行为出现在具有非调节的不对称耦合的耦合的光谐振器的晶格中，这是由于非线性增益饱和与非铁皮皮肤效应之间的相互作用引起的。在频域和时域模拟中都观察到单模激光。它对现场障碍非常强大，并扩展到大型晶格尺寸。该发现可能对实现高功率激光阵列有用。
Single-mode operation is a desirable but elusive property for lasers operating at high pump powers. Typically, single-mode lasing is attainable close to threshold, but increasing the pump power gives rise to multiple lasing peaks due to inter-modal gain competition. We propose a laser with the opposite behavior: multi-mode lasing occurs at low output powers, but pumping beyond a certain value produces a single lasing mode, with all other candidate modes experiencing negative effective gain. This behavior arises in a lattice of coupled optical resonators with non-fine-tuned asymmetric couplings, and is caused by an interaction between nonlinear gain saturation and the non-Hermitian skin effect. The single-mode lasing is observed in both frequency domain and time domain simulations. It is robust against on-site disorder, and scales up to large lattice sizes. This finding might be useful for implementing high-power laser arrays.
