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arXiv:2510.08693 · Physical Review Letters

Single-Shot Conditional Displacement Gate between a Trapped Atom and Traveling Light

Seigo Kikura, Hayato Goto, Fumiya Hanamura, Takao Aoki

Published Apr 17, 2026• 0 citations
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Abstract

We propose a single-shot conditional displacement gate between a trapped atom as the control qubit and a traveling light pulse as the target oscillator, mediated by an optical cavity. Classical driving of the atom synchronized with the light reflection off the cavity realizes the single-shot implementation of the crucial gate for the universal control of hybrid systems. We further derive a concise gate model incorporating cavity loss and atomic decay, facilitating the evaluation and optimization of the gate performance. This proposal establishes a key practical tool for coherently linking stationary atoms with itinerant light, a capability essential for realizing hybrid quantum information processing.

DOI
10.1103/234l-q12q

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