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Jianwei, Pan

Publications and source records attributed to Jianwei, Pan.

Fully integrated InGaAs/InP single-photon detector module with gigahertz sine wave gating

InGaAs/InP single-photon avalanche diodes (SPADs) working in the regime of GHz clock rates are crucial components for the high-speed quantum key distribution (QKD). We have developed for the first time a compact, stable, and user-friendly tabletop InGaAs/InP single-photon detector system operating at a 1.25 GHz gate rate that fully integrates functions for controlling and optimizing SPAD performance. We characterize the key parameters of the detector system and test the long-term stability of the system for continuous operation of 75 h. The detector system can substantially enhance QKD performance and our present work paves the way for practical high-speed QKD applications.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Transverse mode revival of a light-compensated quantum memory

A long-lived quantum memory was developed based on light-compensated cold {sup 87}Rb atoms in a dipole trap. The lifetime of the quantum memory was improved by 40 folds, from 0.67 to 28 ms with the help of a compensation laser beam. Oscillations of the memory efficiency due to the transverse mode breathing of the singly excited spin wave have been clearly observed and clarified with a Monte Carlo simulation procedure. With detailed analysis of the decoherence processes of the spin wave in cold atomic ensembles, this experiment provides a benchmark for the further development of high-quality quantum memories.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Deterministic spin-wave interferometer based on the Rydberg blockade

The spin-wave (SW) N-particle path-entangled |N,0>+|0,N> (NOON) state is an N-particle Fock state with two atomic spin-wave modes maximally entangled. Attributed to the property that the phase is sensitive to collective atomic motion, the SW NOON state can be utilized as an atomic interferometer and has promising application in quantum enhanced measurement. In this paper we propose an efficient protocol to deterministically produce the atomic SW NOON state by employing the Rydberg blockade. Possible errors in practical manipulations are analyzed. A feasible experimental scheme is suggested. Our scheme is far more efficient than the recent experimentally demonstrated one, which only creates a heralded second-order SW NOON state.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗