Anderson light localization is known to be minimally affected by nonlinearity (e.g., gain), as a lasing mode typically arises from an isolated localized mode in a passive system. However, in the Anderson localized regime of low-dimensional systems, local resonances can occasionally experience strong level overlap and form an asymmetric single line, which is also known as necklace states. This case is not a hypothetically rare event and indeed is not uncommon. For such passive transport, we experimentally and theoretically investigate how nonlinearity affects necklace states in multilayered systems. When gain or amplifying media are introduced in a system, an asymmetric line splits into multiple lasing peaks, interacting with one another. By decomposing field spectra into a sum of Lorentzian lines, we find that diverging lasing peaks arise from quasimodes; in turn the lifetime and degree of level overlap of the underlying quasimodes are strongly attributed to the threshold and spectral behavior of the emerging lasing modes. These results suggest that observation of lasing interactions could be an alternative yet powerful tool for investigating necklace states (or hybridized states of coupled resonances), the existence of which is challenging to experimentally prove and study, due to grossly single-appearing spectral peaks in passive systems.

中文翻译：

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激光相互作用揭示了安德森本地化体制下项链国家的隐藏模式

众所周知，安德森光定位受非线性（例如增益）的影响最小，因为激光模式通常源于无源系统中的隔离式本地模式。但是，在低维系统的安德森局部化方案中，局部共振有时会遇到很强的水平重叠并形成不对称的单线，这也称为项链状态。这种情况不是假设的罕见事件，而且确实不少见。对于这种被动传输，我们在实验和理论上研究了非线性如何影响多层系统中的项链状态。当将增益或放大介质引入系统时，一条不对称的线会分裂为多个激光峰，彼此相互作用。通过将场谱分解成洛伦兹线的总和，我们发现发散的激射峰是由准模引起的。反过来，基本准模的寿命和水平重叠的程度强烈地归因于出现的激光模的阈值和光谱行为。这些结果表明，对激射相互作用的观察可能是研究项链状态（或耦合共振的杂化状态）的另一种有效的工具，但由于被动出现的光谱峰总体上单一出现，因此其存在的挑战性难以通过实验证明和研究。系统。