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arXiv · 1511.00702

Stabilizing entanglement via symmetry-selective bath engineering in superconducting qubits

M. E. Schwartz·L. Martin·E. Flurin·C. Aron·M. Kulkarni·H. E. Tureci·I. Siddiqi
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Abstract

Bath engineering, which utilizes coupling to lossy modes in a quantum system to generate non-trivial steady states, is a tantalizing alternative to gate- and measurement-based quantum science. Here, we demonstrate dissipative stabilization of entanglement between two superconducting transmon qubits in a symmetry-selective manner. We utilize the engineered symmetries of the dissipative environment to stabilize a target Bell state; we further demonstrate suppression of the Bell state of opposite symmetry due to parity selection rules. This implementation is resource-efficient, achieves a steady-state fidelity $\mathcal{F} = 0.70$, and is scalable to multiple qubits.

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M. E. Schwartz, L. Martin, E. Flurin, C. Aron, M. Kulkarni, H. E. Tureci, I. Siddiqi. 2015-11-02. Stabilizing entanglement via symmetry-selective bath engineering in superconducting qubits. https://doi.org/10.1103/physrevlett.116.240503

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