arXiv subjects

He-bin Zhang

Publications and source records attributed to He-bin Zhang.

6 recordsLinked to original sources

arXiv2026

Nuclear Spin Squeezing Based on Spin-Exchange Collisions

Isolation from environment leads to the days-long lifetime of noble-gas nuclear spins, but also brings great challenges to the preparation, manipulation, and measurement of nuclear-spin quantum states. Here we find that nuclear spin squeezing, with ultra-long lifetime and huge atomic number, can be efficiently obtained and manipulated based on the coherent spin-exchange interaction between alkali-metal and noble-gas ensembles. Thanks to the considerable advantage of our proposal in preparing the spin squeezing of the macroscopic atomic ensemble with a huge atomic number, even the nuclear spin-squeezed state containing 10^20 atoms or more is obtainable with preexisting techniques. Further, the days-long storage and measurement of nuclear spin squeezing can be performed by the coherent manipulation of a magnetic field. This proposal can be implemented in hot atomic ensembles, whose ease of access and high adaptability to various environments will significantly facilitate the research and application of nuclear-spin nonclassical states in precision measurement, quantum information, and fundamental physics.

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arXiv2025

Nuclear Spin Induced Transparency

Electromagnetically induced transparency (EIT) is an important quantum optical phenomenon which provides a crucial tool for light manipulation. However, typically the transparency window is broad, limited by the coherence time of the metastable state. Here we show that extremely narrow transparency window can be realized using nuclear spin induced transparency (NSIT), which is achieved by combining optical field, magnetic field and the spin-exchange interaction between noble-gas nuclear spins and alkali-metal electronic spins. The width of the NSIT window can be several orders of magnitude smaller than that of conventional EIT, and even reaches sub-mHz range due to the long coherence time of nuclear spins. The scheme holds great potential for applications in slow light and magnetic field sensing.

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arXiv2024

Ultrastrong photon superbunching from electron shelving and time integral

Photon correlation is at the heart of quantum optics and has important applications in quantum technologies. Here we propose a universally applicable mechanism that can generate the superbunching light with ultrastrong second-order and higher-order correlations hitherto unreachable. This mechanism arises from the combined effect of electron shelving and time integral of fluorescence based on a cascaded quantum system comprising an emitter and a filter or a cavity QED system, and has high experimental feasibility according to current experimental techniques. Besides, both the correlation degrees and the frequency of the light can be flexibly varied over broad ranges. Both the research and technological applications on strong correlations can be extensively facilitated due to this readily accessible and manipulated mechanism for generating photon correlation.

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arXiv2023

Nonlinear time-reversal interferometry with arbitrary quadratic collective-spin interaction

Atomic nonlinear interferometry has wide applications in quantum metrology and quantum information science. Here we propose a nonlinear time-reversal interferometry scheme with high robustness and metrological gain based on the spin squeezing generated by arbitrary quadratic collective-spin interaction, which could be described by the Lipkin-Meshkov-Glick (LMG) model. We optimize the squeezing process, encoding process, and anti-squeezing process, finding that the two particular cases of the LMG model, one-axis twisting and two-axis twisting outperform in robustness and precision, respectively. Moreover, we propose a Floquet driving method to realize equivalent time reverse in the atomic system, which leads to high performance in precision, robustness, and operability. Our study sets a benchmark in achieving high precision and robustness in atomic nonlinear interferometry.

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arXiv2023

Spin Squeezing with Arbitrary Quadratic Collective-Spin Interaction

Spin squeezing is vitally important in quantum metrology and quantum information science. The noise reduction resulting from spin squeezing can surpass the standard quantum limit and even reach the Heisenberg Limit (HL) in some special circumstances. However, systems that can reach the HL are very limited. Here we study the spin squeezing in atomic systems with a generic form of quadratic collective-spin interaction, which can be described by the Lipkin-Meshkov-Glick(LMG) model. We find that the squeezing properties are determined by the initial states and the anisotropic parameters. Moreover, we propose a pulse rotation scheme to transform the model into two-axis twisting model with Heisenberg-limited spin squeezing. Our study paves the way for reaching HL in a broad variety of systems.

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arXiv2021

Subnatural-linewidth fluorescent single photons

Subnatural-linewidth single photons are ofvital importance in quantum optics and quantum information science. According to previous research, it appears difficult to utilize resonance fluorescence to generate single photons with subnatural linewidth. Here we propose a universally applicable approach to generate fluorescent single photons with subnatural linewidth, which can be implemented based on {\Lambda}-shape and similar energy structures. Further, the general condition to obtain fluorescent single photons with subnatural linewidth is revealed. The single-photon linewidth can be easily manipulated over a broad range by external fields, which can be several orders ofmagnitude smaller than the natural linewidth. Our study can be easily implemented in various physical platforms with current experimental techniques and will significantly facilitate the research on the quantum nature of resonance fluorescence and the technologies in quantum information science.

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