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arXiv · 2401.09279

Shallow quantum circuits are robust hunters for quantum many-body scars

Gabriele Cenedese·Maria Bondani·Alexei Andreanov·Matteo Carrega·Giuliano Benenti·Dario Rosa
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Abstract

Presently, noisy intermediate-scale quantum computers encounter significant technological challenges that make it impossible to generate large amounts of entanglement. We leverage this technological constraint as a resource and demonstrate that a shallow variational eigensolver can be trained to successfully target quantum many-body scar states. Scars are area-law high-energy eigenstates of quantum many-body Hamiltonians, which are sporadic and immersed in a sea of volume-law eigenstates. We show that the algorithm is robust and can be used as a versatile diagnostic tool to uncover quantum many-body scars in arbitrary physical systems.

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Gabriele Cenedese, Maria Bondani, Alexei Andreanov, Matteo Carrega, Giuliano Benenti, Dario Rosa. 2024-01-17. Shallow quantum circuits are robust hunters for quantum many-body scars. https://arxiv.org/abs/2401.09279

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