arXiv subjects

Yun-Lan Zuo

Publications and source records attributed to Yun-Lan Zuo.

6 recordsLinked to original sources

arXiv2026

Two-Polariton Blockade via Ultrastrong Light-Matter Coupling

We demonstrate that a two-polariton blockade (2PB) can occur under resonant single-polariton driving in an atom-cavity system operating in the ultrastrong coupling (USC) regime-a phenomenon qualitatively distinct from, and unattainable in, both the strong and weak coupling regimes. In the USC regime, where the ratio of the atom-cavity coupling strength to the cavity resonance frequency exceeds 0.1, hybrid light-matter quasiparticles known as polaritons emerge. By employing modified second- and third-order correlation functions appropriate for the USC regime, we predict the emergence of 2PB, characterized by pronounced two-polariton bunching accompanied by suppressed three-polariton coincidences. This Letter introduces a novel route to achieving 2PB, with promising implications for the realization of multiparticle quantum light sources in the USC regime.

quant-ph↗

arXiv2025

Phase-selective tripartite entanglement and asymmetric Einstein-Podolsky-Rosen steering in squeezed optomechanics

The generation and manipulation of multipartite entanglement and EPR steering in macroscopic systems not only play a fundamental role in exploring the nature of quantum mechanics, but are also at the core of current developments of various nascent quantum technologies. Here we report a theoretical method using squeezing-phase-controlled quantum noise flows to selectively generate and manipulate quantum entanglement and asymmetric EPR steering in a nonlinear $χ^{(2)}$ whispering-gallery-mode (WGM) optomechanical resonator. We show that by pumping the $χ^{(2)}$ nonlinear medium with two-photon optical fields and broadband squeezed lights, a pair of counterpropagating squeezed optical modes could be introduced to the WGM resonator, each coupled with an independent squeezed vacuum reservoir. This configuration could enable squeezing-phase-controlled light-reservoir interaction for each squeezed optical mode, providing a flexible tool for tailoring asymmetric optical noise flows in the counterpropagating modes. Based on this unique feature, it is found that with the injection of asymmetric noise flows, the generation of various types of bipartite and tripartite entanglement become phase-dependent and thus they can be produced in an asymmetric way. More excitingly, it is also found that by further properly adjusting the squeezing parameters, the overall asymmetry of EPR steering can also be stepwise driven from no-way regime, one-way regime to two-way regime. These findings, holding promise for preparing rich types of entangled quantum resources with asymmetric features, may have potential applications in the area of secure quantum information processing such as quantum secure direct communication and one-way quantum computing.

quant-ph↗

arXiv2024

Achieving Robust Single-Photon Blockade with a Single Nanotip

Backscattering losses, due to intrinsic imperfections or external perturbations that are unavoidable in optical resonators, can severely affect the performance of practical photonic devices. In particular, for quantum single-photon devices, robust quantum correlations against backscattering losses, which are highly desirable for diverse applications, have remained largely unexplored. Here, we show that single-photon blockade against backscattering loss, an important purely quantum effect, can be achieved by introducing a nanotip near a Kerr nonlinear resonator with intrinsic defects. We find that the quantum correlation of single photons can approach that of a lossless cavity even in the presence of strong backscattering losses. Moreover, the behavior of such quantum correlation is distinct from that of the classical mean-photon number with different strengths of the nonlinearity, due to the interplay of the resonator nonlinearity and the tip-induced optical coupling. Our work sheds new light on protecting and engineering fragile quantum devices against imperfections, for applications in robust single-photon sources and backscattering-immune quantum devices.

quant-ph↗

arXiv2024

Tripartite quantum entanglement with squeezed optomechanics

The ability to engineer entangled states that involve macroscopic objects is of particular importance for a wide variety of quantum-enabled technologies, ranging from quantum information processing to quantum sensing. Here we propose how to achieve coherent manipulation and enhancement of quantum entanglement in a hybrid optomechanical system, which consists of a Fabry-Pérot cavity with two movable mirrors, an optical parametric amplifier (OPA), and an injected squeezed vacuum reservoir. We show that the advantages of this system are twofold: (i) one can effectively regulate the light-mirror interactions by introducing a squeezed intracavity mode via the OPA; (ii) when properly matching the squeezing parameters between the squeezed cavity mode and the injected squeezed vacuum reservoir, the optical input noises can be suppressed completely. These peculiar features of this system allow us to generate and manipulate quantum entanglement in a coherent and controllable way. More importantly, we also find that such controllable entanglement, under some specific squeezing parameters, can be considerably enhanced in comparison with those of the conventional optomechanical system. Our work, providing a promising method to regulate and tailor the light-mirror interaction, are poised to serve as a useful tool for engineering various quantum effects which are based on cavity optomechanics.

quant-ph↗

arXiv2024

Squeezing-enhanced quantum sensing with quadratic optomechanics

Cavity optomechanical (COM) sensors, enhanced by quantum squeezing or entanglement, have become powerful tools for measuring ultra-weak forces with high precision and sensitivity. However, these sensors usually rely on linear COM couplings, a fundamental limitation when measurements of the mechanical energy are desired. Very recently, a giant enhancement of the signal-to-noise ratio was predicted in a quadratic COM system. Here we show that the performance of such a system can be further improved surpassing the standard quantum limit by using quantum squeezed light. Our approach is compatible with available engineering techniques of advanced COM sensors and provides new opportunities for using COM sensors in tests of fundamental laws of physics and quantum metrology applications.

quant-ph↗

arXiv2021

Vector optomechanical entanglement

The polarizations of optical fields, besides field intensities, provide more degrees of freedom to manipulate coherent light-matter interactions. Here we propose how to achieve a coherent switch of optomechanical entanglement in a polarized-light-driven cavity system. We show that by tuning the polarizations of the driving field, the effective optomechanical coupling can be well controlled and, as a result, quantum entanglement between the mechanical oscillator and the optical transverse electric (TE) mode can be coherently and reversibly switched to that between the same phonon mode and the optical transverse magnetic (TM) mode. This ability of switching optomechanical entanglement with such a vectorial device can be important for building a quantum network being capable of efficient quantum information interchanges between processing nodes and flying photons.

quant-ph↗