论文标题
Chern绝缘子附近的量子发射极的自发发射：时间逆转对称性的相互作用和范·霍夫（Van Hove）的奇异性
Spontaneous emission of a quantum emitter near a Chern insulator: interplay of time reversal symmetry breaking and van Hove singularity
论文作者
论文摘要
我们考虑了偶极子近似中二维Chern绝缘子附近的二级量子发射极的通用问题，并研究绝缘体的频率依赖性响应和电子密度如何修改地面和激发水平之间的发射器的过渡速率。为此，我们通过基于Qi-Wu-Zhang模型进行紧密结合计算并使用Kubo公式来获得电导率张量的完整实际频率行为，并得出了系统的完整电磁绿色张量，从而破坏OnSager互惠性。这使我们能够发现，对于小于最大带隙的频率，该系统对时间逆转对称性的破坏敏感，而对于更大的频率，系统变得不敏感，这对歧视循环极化偶极子的状态的影响含义。我们还研究了Van Hove奇点对表面诱导的校正对过渡速率的影响，发现与将电导率设置为静态值相比，它可以提高其幅度几个数量级。通过考虑偶极子是圆形极化或与Chern绝缘子表面平行的构型，我们发现对过渡速率的表面校正可以表现出具有正弦积分样振荡的新颖衰变。
We consider the generic problem of a two-level quantum emitter near a two-dimensional Chern insulator in the dipole approximation, and study how the frequency-dependent response and electronic density of states of the insulator modifies the transition rate of the emitter between the ground and excited levels. To this end, we obtain the full real-frequency behavior of the conductivity tensor by performing a tight-binding calculation based on the Qi-Wu-Zhang model and using a Kubo formula, and derive the full electromagnetic Green tensor of the system, which breaks Onsager reciprocity. This enables us to find that for frequencies smaller than the maximum band gap, the system is sensitive to time reversal symmetry-breaking, whereas for much larger frequencies the system becomes insensitive, with implications for the discrimination of the state of a circularly polarised dipole emitter. We also study the impact of a van Hove singularity on the surface-induced correction to the transition rate, finding that it can enhance its amplitude by a few orders of magnitude compared to the case where the conductivity is set to its static value. By considering configurations in which the dipole is circularly polarised or parallel with the surface of the Chern insulator, we find that the surface correction to the transition rate can exhibit a novel decay with sine integral-like oscillations.
