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arXiv · 1809.03571

Autonomous Quantum State Transfer by Dissipation Engineering

Chen Wang·Jeffrey M. Gertler
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Abstract

Quantum state transfer from an information-carrying qubit to a receiving qubit is ubiquitous for quantum information technology. In a closed quantum system, this task requires precisely-timed control of coherent qubit-qubit interactions that are intrinsically reciprocal. Here, breaking reciprocity by tailoring dissipation in an open system, we show that it is possible to autonomously transfer a quantum state between stationary qubits without time-dependent control. We present the general requirements for this directional transfer process, and show that the minimum system dimension for transferring one qubit of information is 3 $\times$ 2 (between one physical qutrit and one physical qubit), plus one auxiliary reservoir. We propose realistic implementations in present-day superconducting circuit QED experiments, and further propose schemes compatible with long-distance state transfer using impedance-matched dissipation engineering.

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Chen Wang, Jeffrey M. Gertler. 2019-10-23. Autonomous Quantum State Transfer by Dissipation Engineering. https://doi.org/10.1103/physrevresearch.1.033198

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