发表机构
Nanyang Technological University（南洋理工大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文研究相互作用对光学跃迁量子几何的影响，发现电子-空穴相互作用可产生均匀平坦的激子量子几何，使非磁性材料的三阶圆光导率归零，并锁定局域跃迁的霍尔响应。
AI 中文摘要
光学跃迁偶极子的黎曼几何已成为理解线性和非线性光学响应的有用图像。在此，我们认为光学跃迁的相互作用量子几何具有丰富的结构，并且可以自然地划分为两种类型：局域化和离域化的粒子-空穴激发。前者具有均匀的量子几何，其厄米曲率平坦（为零）；后者具有非均匀的量子几何，其厄米曲率不为零。作为一个引人注目的例子，我们发现均匀的量子几何可以由电子-空穴相互作用产生：即使由粒子带和空穴带中的扩展布洛赫态组成，激子也具有均匀且平坦的量子几何。通过发展非线性响应的多体长度规范表述，我们发现这种均匀且平坦的激子量子几何在非磁性材料中使其三阶圆光导率归零，与其非相互作用对应物形成鲜明对比。类似地，局域化光学跃迁的零厄米曲率将其霍尔响应锁定为基态的霍尔响应。这展示了由相互作用量子几何控制的多体光学响应的丰富景观。
英文摘要
The Riemannian geometry of optical transition dipoles has become a useful picture for understanding linear and nonlinear optical response. Here we argue that the interacting quantum geometry of optical transitions possesses a rich structure and can be naturally delineated into two types: localized and delocalized particle-hole excitations. The former possess uniform quantum geometry with flat (vanishing) Hermitian curvature; the latter possess non-uniform quantum geometry with non-vanishing Hermitian curvature. As a striking example, we find that uniform quantum geometry can be produced by electron-hole interactions: even when composed from extended Bloch states in the particle and hole bands, we find excitons have uniform and flat quantum geometry. By developing a many-body length gauge formulation of nonlinear response, we find this uniform and flat excitonic quantum geometry zeros its third-order circular photoconductivity in non-magnetic materials in stark contrast to its non-interacting counterparts. Similarly, the zero Hermitian curvature of localized optical transitions locks their Hall response to that of the ground state. This demonstrates the rich landscape of many-body optical response controlled by an interacting quantum geometry.
Comments19 pages, 2 figures
