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 transfer a quantum state between stationary qubits autonomously 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.

• Received 9 September 2018

DOI:https://doi.org/10.1103/PhysRevResearch.1.033198

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Published by the American Physical Society