Abstract Nonlinear interactions in many physical systems lead to symmetry breaking phenomena in which an initial spatially homogeneous stationary solution becomes modulated. Modulation instabilities have been widely studied since the 1960s in different branches of nonlinear physics. In optics, they may result in the formation of optical solitons, localized structures that maintain their shape as they propagate, which have been investigated in systems ranging from optical fibres to passive microresonators. Recently, a generalized version of the Lugiato–Lefever equation predicted their existence in ring quantum cascade lasers with an external driving field, a configuration that enables the bistability mechanism at the basis of the formation of optical solitons. Here, we consider this driven emitter and extensively study the structures emerging therein. The most promising regimes for localized structure formation are assessed by means of a linear stability analysis of the homogeneous stationary solution (or continuous-wave solution). In particular, we show the existence of phase solitons – chiral structures excited by phase jumps in the cavity – and cavity solitons. The latter can be deterministically excited by means of writing pulses and manipulated by the application of intensity gradients, making them promising as frequency combs (in the spectral domain) or reconfigurable bit sequences that can encode information inside the ring cavity.

中文翻译：

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具有注入信号的环形量子级联激光器的孤子动力学

摘要 许多物理系统中的非线性相互作用会导致对称破坏现象，其中初始空间均匀的平稳解被调制。自 1960 年代以来，在非线性物理学的不同分支中，调制不稳定性已被广泛研究。在光学中，它们可能导致形成光孤子，即在传播时保持其形状的局部结构，这已在从光纤到无源微谐振器的系统中进行了研究。最近，Lugiato-Lefever 方程的广义版本预测了它们在具有外部驱动场的环形量子级联激光器中的存在，这种配置在形成光孤子的基础上实现了双稳态机制。这里，我们考虑这个驱动发射器并广泛研究其中出现的结构。最有希望的局部结构形成机制是通过对均匀固定解（或连续波解）的线性稳定性分析来评估的。特别是，我们展示了相位孤子（由腔中的相位跳跃激发的手性结构）和腔孤子的存在。后者可以通过写入脉冲确定性地激发，并通过应用强度梯度进行操纵，使它们有希望作为频率梳（在谱域中）或可重构位序列，可以对环形腔内的信息进行编码。最有希望的局部结构形成机制是通过对均匀固定解（或连续波解）的线性稳定性分析来评估的。特别是，我们展示了相位孤子（由腔中的相位跳跃激发的手性结构）和腔孤子的存在。后者可以通过写入脉冲确定性地激发，并通过应用强度梯度进行操纵，使它们有希望作为频率梳（在谱域中）或可重构位序列，可以对环形腔内的信息进行编码。最有希望的局部结构形成机制是通过对均匀固定解（或连续波解）的线性稳定性分析来评估的。特别是，我们展示了相位孤子（由腔中的相位跳跃激发的手性结构）和腔孤子的存在。后者可以通过写入脉冲确定性地激发，并通过应用强度梯度进行操纵，使它们有希望作为频率梳（在谱域中）或可重构位序列，可以对环形腔内的信息进行编码。