论文标题
通过辅助量子探测光系统的对称破坏
Probing the symmetry breaking of a light--matter system by an ancillary qubit
论文作者
论文摘要
Ultrastrong中的混合量子系统，甚至在深度，耦合方案中甚至更多的量子系统可以表现出异国的物理现象，并有望在量子技术中使用新的应用。在这些非扰动状态中，Qubit-resonator系统具有纠缠的量子真空，在谐振器中具有非零的平均光子数，在谐振器中，光子是虚拟的，无法直接检测到。然而，真空场能够诱导分散耦合探针量子的对称破裂。我们通过实验观察到由集体元素超导谐振剂与通量乘量子耦合的集体元素超导谐振器诱导的辅助XMON人工原子的平均对称性破裂。该结果开辟了一种实验探索在深度耦合方面出现的新型量子效应效应的方法。
Hybrid quantum systems in the ultrastrong, and even more in the deep-strong, coupling regimes can exhibit exotic physical phenomena and promise new applications in quantum technologies. In these nonperturbative regimes, a qubit--resonator system has an entangled quantum vacuum with a nonzero average photon number in the resonator, where the photons are virtual and cannot be directly detected. The vacuum field, however, is able to induce the symmetry breaking of a dispersively coupled probe qubit. We experimentally observe the parity symmetry breaking of an ancillary Xmon artificial atom induced by the field of a lumped-element superconducting resonator deep-strongly coupled with a flux qubit. This result opens a way to experimentally explore the novel quantum-vacuum effects emerging in the deep-strong coupling regime.
