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arXiv · 2203.11975

Finite-depth scaling of infinite quantum circuits for quantum critical points

Bernhard Jobst·Adam Smith·Frank Pollmann
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Abstract

The scaling of the entanglement entropy at a quantum critical point allows us to extract universal properties of the state, e.g., the central charge of a conformal field theory. With the rapid improvement of noisy intermediate-scale quantum (NISQ) devices, these quantum computers present themselves as a powerful tool to study critical many-body systems. We use finite-depth quantum circuits suitable for NISQ devices as a variational ansatz to represent ground states of critical, infinite systems. We find universal finite-depth scaling relations for these circuits and verify them numerically at two different critical points, i.e., the critical Ising model with an additional symmetry-preserving term and the critical XXZ model.

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Bernhard Jobst, Adam Smith, Frank Pollmann. 2022-03-22. Finite-depth scaling of infinite quantum circuits for quantum critical points. https://doi.org/10.1103/physrevresearch.4.033118

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