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arXiv · 1910.01204

Diffusive entanglement generation by continuous homodyne monitoring of spontaneous emission

Philippe Lewalle·Cyril Elouard·Sreenath K. Manikandan·Xiao-Feng Qian·Joseph H. Eberly·Andrew N. Jordan
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Abstract

We consider protocols to generate quantum entanglement between two remote qubits, through joint time-continuous detection of their spontaneous emission. We demonstrate that schemes based on homodyne detection, leading to diffusive quantum trajectories, lead to identical average entanglement yield as comparable photodetection strategies; this is despite substantial differences in the two-qubit state dynamics between these schemes, which we explore in detail. The ability to use different measurements to achieve the same ends may be of practical significance; the less-well-known diffusive scheme appears far more feasible on superconducting qubit platforms in the near term.

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Philippe Lewalle, Cyril Elouard, Sreenath K. Manikandan, Xiao-Feng Qian, Joseph H. Eberly, Andrew N. Jordan. 2019-10-02. Diffusive entanglement generation by continuous homodyne monitoring of spontaneous emission. https://arxiv.org/abs/1910.01204

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