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arXiv · 2410.06250

Statistics of topological defects across a phase transition in a digital superconducting quantum processor

Oriel Kiss·Daniil Teplitskiy·Michele Grossi·Antonio Mandarino
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Abstract

When a quantum phase transition is crossed within a finite time, critical slowing down disrupts adiabatic dynamics, resulting in the formation of topological defects. The average density of these defects scales with the quench rate, adhering to a universal power law as predicted by the Kibble-Zurek mechanism (KZM). In this study, we aim to investigate the counting statistics of kink density in the 1D transverse-field quantum Ising model. We demonstrate on multiple quantum processing units up to 100 qubits, that higher-order cumulants follow a universal power law scaling as a function of the quench time. We also show the breakdown of the KZM for short quenches for finite-size systems. Tensor network simulations corroborate our quantum simulation results for bigger systems not in the asymptotic limit.

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Oriel Kiss, Daniil Teplitskiy, Michele Grossi, Antonio Mandarino. 2024-10-08. Statistics of topological defects across a phase transition in a digital superconducting quantum processor. https://doi.org/10.1088/2058-9565%2Faddf75

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