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arXiv · 1804.07591

Single-loop realization of arbitrary non-adiabatic holonomic single-qubit quantum gates in a superconducting circuit

Y. Xu·W. Cai·Y. Ma·X. Mu·L. Hu·Tao Chen·H. Wang·Y. P. Song·Zheng-Yuan Xue·Zhang-qi Yin·L. Sun
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Abstract

Geometric phases are noise-resilient, and thus provide a robust way towards high fidelity quantum manipulation. Here we experimentally demonstrate arbitrary non-adiabatic holonomic single-qubit quantum gates for both a superconducting transmon qubit and a microwave cavity in a single-loop way. In both cases, an auxiliary state is utilized, and two resonant microwave drives are simultaneously applied with well-controlled but varying amplitudes and phases for the arbitrariness of the gate. The resulting gates on the transmon qubit achieve a fidelity of 0.996 characterized by randomized benchmarking and the ones on the cavity show an averaged fidelity of 0.978 based on a full quantum process tomography. In principle, a nontrivial two-qubit holonomic gate between the qubit and the cavity can also be realized based on our presented experimental scheme. Our experiment thus paves the way towards practical non-adiabatic holonomic quantum manipulation with both qubits and cavities in a superconducting circuit.

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Y. Xu, W. Cai, Y. Ma, X. Mu, L. Hu, Tao Chen, H. Wang, Y. P. Song, Zheng-Yuan Xue, Zhang-qi Yin, L. Sun. 2018-04-20. Single-loop realization of arbitrary non-adiabatic holonomic single-qubit quantum gates in a superconducting circuit. https://doi.org/10.1103/physrevlett.121.110501

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