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arXiv · 1909.09766

Deterministic generation and partial retrieval of a spin-wave excitation in an atomic ensemble

Shengzhi Wang·Zhongxiao Xu·Dengxin Wang·Yafei Wen·Minjie Wang·Pai Zhou·Liang Yuan·Shujing Li·Hai Wang
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Abstract

In this paper, we report a generation of a spin-wave excitation (SWE) with a near-unity () probability in a given time (~730). Such deterministic generation relies on a feedback scheme with a millisecond quantum memory. The millisecond memory is achieved by maximizing the wavelength of the spin wave and storing the SWE as the magnetic-field-insensitive transition. We then demonstrate partial retrievals of the spin wave by applying a first read pulse whose area is smaller than the value of . The remained SWE is fully retrieved by a second pulse. Anti-correlation function between the detections in the first and second readouts has been measured, which shows that the partial-retrieval operation on the SWE is in the quantum regime. The presented experiment represents an important step towards the realization of the improved DLCZ quantum repeater protocol proposed in Phys. Rev. A 77, 062301 (2008).

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Shengzhi Wang, Zhongxiao Xu, Dengxin Wang, Yafei Wen, Minjie Wang, Pai Zhou, Liang Yuan, Shujing Li, Hai Wang. 2019-09-21. Deterministic generation and partial retrieval of a spin-wave excitation in an atomic ensemble. https://doi.org/10.1364/oe.27.027409

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