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arXiv · 2404.02957

Spatiotemporal Quenches for Efficient Critical Ground State Preparation in Two-Dimensional Quantum Systems

Simon Bernier·Kartiek Agarwal
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Abstract

Quantum simulators have the potential to shed light on the study of quantum many-body systems and materials, offering unique insights into various quantum phenomena. While adiabatic evolution has been conventionally employed for state preparation, it faces challenges when the system evolves too quickly or the coherence time is limited. In such cases, shortcuts to adiabaticity, such as spatiotemporal quenches, provide a promising alternative. This paper numerically investigates the application of spatiotemporal quenches in the two-dimensional transverse field Ising model with ferromagnetic interactions, focusing on the emergence of the ground state and its correlation properties at criticality when the gap vanishes. We demonstrate the effectiveness of these quenches in rapidly preparing ground states in critical systems. Our simulations reveal the existence of an optimal quench front velocity at the emergent speed of light, leading to minimal excitation energy density and correlation lengths of the order of finite system sizes we can simulate. These findings emphasize the potential of spatiotemporal quenches for efficient ground state preparation in quantum systems, with implications for the exploration of strongly correlated phases and programmable quantum computing.

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Simon Bernier, Kartiek Agarwal. 2024-04-03. Spatiotemporal Quenches for Efficient Critical Ground State Preparation in Two-Dimensional Quantum Systems. https://arxiv.org/abs/2404.02957

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