Magnetic-free optical non-reciprocal components, such as isolators and circulators, are highly desirable for on-chip optical signal processing^1,2 and quantum networks^3,4. However, their realization presents a fundamental difficulty due to the Lorentz reciprocity in most optical devices⁵. In this study, we propose and experimentally realize optical non-reciprocity with atoms embedded in a ring cavity at room temperature. Random thermal motion of atoms, in the presence of a unidirectional control field, creates susceptibility–momentum locking, and subsequently a new type of chiral quantum optical system. Furthermore, we demonstrate strong non-reciprocity based on this chiral quantum system in the regime of collectively strong atom–cavity coupling. Our scheme provides a new routine towards the realization of chiral quantum optics and chip-compatible, non-magnetic optical non-reciprocity.

对于片上光信号处理^1,2和量子网络^3,4，非常需要无磁的光学不可逆组件，例如隔离器和循环器。然而，由于大多数光学设备中的洛仑兹互易性，实现它们的过程存在根本的困难⁵。在这项研究中，我们提出并通过实验实现了室温下嵌入环腔中的原子的光学不可逆性。在单向控制场的存在下，原子的随机热运动会产生磁化率－动量锁定，进而产生一种新型的手性量子光学系统。此外，我们证明了基于这种手性量子系统的强不可逆性，这种强不可逆性是在集体强原子-空穴耦合的状态下进行的。我们的方案为实现手性量子光学和芯片兼容的非磁性非互易性提供了新的程序。