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arXiv · 2203.04978

Parameterized Two-Qubit Gates for Enhanced Variational Quantum Eigensolver

S. E. Rasmussen·N. T. Zinner
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Abstract

The variational quantum eigensolver is a prominent hybrid quantum-classical algorithm expected to impact near-term quantum devices. They are usually based on a circuit ansatz consisting of parameterized single-qubit gates and fixed two-qubit gates. We study the effect of parameterized two-qubit gates in the variational quantum eigensolver. We simulate a variational quantum eigensolver algorithm using fixed and parameterized two-qubit gates in the circuit ansatz and show that the parameterized versions outperform the fixed versions, both when it comes to best energy and reducing outliers, for a range of Hamiltonians with applications in quantum chemistry and materials science.

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S. E. Rasmussen, N. T. Zinner. 2022-10-12. Parameterized Two-Qubit Gates for Enhanced Variational Quantum Eigensolver. https://doi.org/10.1002/andp.202200338

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