探测超强耦合超导量子电路中的虚光子
Detecting virtual photons in ultrastrongly coupled superconducting quantum circuits
AI总结：
针对超强耦合电路基态虚光子长期难以探测的问题，论文提出用光 fluxonium qudit 与相干控制将虚光子选择性转化为实光子，从而以现有技术实现高保真探测。
摘要：
光与物质的相互作用以及理解其背后的基础物理，对于新兴量子技术至关重要。固态器件可以探索耦合强度达到“超强”的新区域，即耦合强度可与各子系统的能量相比拟。此时会出现新的奇异现象，其中许多现象的共同根源在于纠缠真空中含有虚光子。这些虚光子预示着激发数守恒的丧失，而这正是超强耦合打破 U(1) 对称性的见证。尽管已有十多年研究，基态虚光子的探测仍有待实验演示。在本工作中，我们识别出一组“相互牵连”的实验挑战，并展示如何克服它们，从而为这一长期存在的问题提供解决方案。我们发现，将基于超电感的非传统“光 fluxonium”qudit 与相干控制相结合，可以高效、忠实且有选择性地把虚光子转化为实光子。这使得利用当今量子技术已具备的资源即可探测它们。
英文摘要：
Light-matter interaction and understanding the fundamental physics behind is essential for emerging quantum technologies. Solid-state devices may explore new regimes where coupling strengths are "ultrastrong", i.e., comparable to the energies of the subsystems. New exotic phenomena occur the common root of many of them being the fact that the entangled vacuum contains virtual photons. They herald the lack of conservation of the number of excitations which is the witness of ultrastrong coupling breaking the U(1) symmetry. Despite more than a decade of research, the detection of ground-state virtual photons still awaits demonstration. In this work, we recognize the "conspiring" set of experimental challenges and show how to overcome them, thus providing a solution to this long-standing problem. We find that combining a superinductor-based unconventional "light fluxonium" qudit and coherent control yields a highly efficient, faithful, and selective conversion of virtual photons into real ones. This enables their detection with resources available to present-day quantum technologies.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
