Structured Cavity Quantum Electrodynamics

Shunfa Liu; Jiantao Ma; Hanqing Liu; Yangpeng Wang; Xueshi Li; Haiqiao Ni; Zhichuan Niu; Kai Zou; Yun Meng; Xiaolong Hu; Xuehua Wang; Jin Liu

arXiv · 2607.21012

Structured Cavity Quantum Electrodynamics

Shunfa Liu·Jiantao Ma·Hanqing Liu·Yangpeng Wang·Xueshi Li·Haiqiao Ni·Zhichuan Niu·Kai Zou·Yun Meng·Xiaolong Hu·Xuehua Wang·Jin Liu

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Abstract

A cavity quantum electrodynamics (cQED) system consisting of a confined single photon and a single quantum emitter serves as a fundamental block for quantum optics and photonic quantum technologies. The canonical optical mode employed in the conventional cavity quantum electrodynamics features a uniform polarization distribution, leading to the scalar light-matter interaction in most existing experiments. Despite the rapid progress in the generation of structured light with spatially varied polarizations, the structured light-matter interaction, especially at the single quanta level, is highly intriguing yet largely unexplored. Here, we present the structured light-matter interaction at the single-photon level in a semiconductor cavity quantum electrodynamics system. Four distinct structured cavity modes that are spectrally close to each other are constructed in a micropillar cavity. By spatially locating a single epitaxial quantum dot (QD) at the periphery of a semiconductor micropillar cavity and spectrally tuning the QD emission wavelength into the resonances of the structured cavity modes, cavity-enhanced single-photon emissions with spin-locked chiral orbital angular momentum (OAM) and engineerable spin-orbit entanglements are achieved within a single wavelength-scale device. Our work opens an unexplored paradigm of structured quantum light-matter interactions and may further advance chiral quantum optics and high-dimensional photonic quantum technology.

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Shunfa Liu, Jiantao Ma, Hanqing Liu, Yangpeng Wang, Xueshi Li, Haiqiao Ni, Zhichuan Niu, Kai Zou, Yun Meng, Xiaolong Hu, Xuehua Wang, Jin Liu. 2026-07-23. Structured Cavity Quantum Electrodynamics. https://arxiv.org/abs/2607.21012

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