由迁移率受限激发产生的动力学诱导序
Kinetically induced order from mobility-constrained excitations
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中文总结 AI 辅助
研究强关联系统中受限激发如何驱动对称破缺长程序，核心方法是通过与局部序参量场耦合激活激发迁移率，经序参量凝聚增加动能来稳定长程序，在自旋链和Kitaev-Kondo模型中验证了该机制。
中文摘要 AI 辅助
强关联系统的一个迷人特征是，激发在某些情况下可能在涌现对称性下携带非平凡量子数，这可能强烈限制其运动。我们表明，这种受限激发可通过动力学机制在驱动对称破缺长程序中发挥核心作用：与局部序参量场耦合激活否则受限激发的迁移率，序参量的凝聚进而使动能大幅增加，从而稳定具有长程序的相。我们在两种情况下说明此机制：（i）具有磁化偶极守恒律的自旋链中的二聚化不稳定性，以及（ii）Kitaev-Kondo模型中电子的巡游磁性，其中电荷载流子与形成自旋液体的局部磁矩耦合。只要存在有限密度的迁移率受限激发，此机制就起作用，无论是通过非平衡制备还是热激活。在后一种情况下，我们认为，反直觉地，升高温度可通过增强热激活激发的动能增加来促进有序。
英文摘要
A fascinating feature of strongly correlated systems is that excitations may carry nontrivial quantum numbers under emergent symmetries which, in some cases, may strongly constrain their motion. We show that such constrained excitations can play a central role in driving symmetry-breaking long-range order through a kinetic mechanism: coupling to a local order-parameter field activates the mobility of otherwise constrained excitations, and condensation of the order parameter then enables a large gain in kinetic energy, thereby stabilizing a phase with long-range order. We illustrate this mechanism in two settings: (i) a dimerization instability in a spin chain with a magnetization dipole conservation law, and (ii) itinerant magnetism of electrons in the Kitaev-Kondo model, where charge carriers couple to local moments that form a spin liquid. This mechanism becomes operative whenever a finite density of mobility-constrained excitations is present, either through non-equilibrium preparation or thermal activation. In the latter case, we argue that increasing temperature can, counterintuitively, promote order by enhancing the kinetic-energy gain of thermally activated excitations.
