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arXiv · 1710.01455

Entangling distant solid-state spins via thermal phonons

Puhao Cao·Ralf Betzholz·Shaoliang Zhang·Jianming Cai
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Abstract

The implementation of quantum entangling gates between qubits is essential to achieve scalable quantum computation. Here, we propose a robust scheme to realize an entangling gate for distant solid-state spins via a mechanical oscillator in its thermal equilibrium state. By appropriate Hamiltonian engineering and usage of a protected subspace, we show that the proposed scheme is able to significantly reduce the thermal effect of the mechanical oscillator on the spins. In particular, we demonstrate that a high entangling gate fidelity can be achieved even for a relatively high thermal occupation. Our scheme can thus relax the requirement for ground-state cooling of the mechanical oscillator, and may find applications in scalable quantum information processing in hybrid solid-state architectures.

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Puhao Cao, Ralf Betzholz, Shaoliang Zhang, Jianming Cai. 2018-01-17. Entangling distant solid-state spins via thermal phonons. https://doi.org/10.1103/physrevb.96.245418

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