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arXiv · 2409.12018

Operator-Projected Variational Quantum Imaginary Time Evolution

Aeishah Ameera Anuar·Francois Jamet·Fabio Gironella·Fedor Simkovic IV·Riccardo Rossi
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Abstract

Variational Quantum Imaginary Time Evolution (VQITE) is a leading technique for ground state preparation on quantum computers. A significant computational challenge of VQITE is the determination of the quantum geometric tensor. We show that requiring the imaginary-time evolution to be correct only when projected onto a chosen set of operators allows to achieve a twofold reduction in circuit depth by bypassing fidelity estimations, and reduces measurement complexity from quadratic to linear in the number of parameters. We demonstrate by a simulation of the transverse-field Ising model that our algorithm achieves a several orders of magnitude improvement in the number of measurements required for the same accuracy.

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Aeishah Ameera Anuar, Francois Jamet, Fabio Gironella, Fedor Simkovic IV, Riccardo Rossi. 2024-09-18. Operator-Projected Variational Quantum Imaginary Time Evolution. https://arxiv.org/abs/2409.12018

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