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arXiv · 2008.10322

Real- and imaginary-time evolution with compressed quantum circuits

Sheng-Hsuan Lin·Rohit Dilip·Andrew G. Green·Adam Smith·Frank Pollmann
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Abstract

The current generation of noisy intermediate scale quantum computers introduces new opportunities to study quantum many-body systems. In this paper, we show that quantum circuits can provide a dramatically more efficient representation than current classical numerics of the quantum states generated under non-equilibrium quantum dynamics. For quantum circuits, we perform both real- and imaginary-time evolution using an optimization algorithm that is feasible on near-term quantum computers. We benchmark the algorithms by finding the ground state and simulating a global quench of the transverse field Ising model with a longitudinal field on a classical computer. Furthermore, we implement (classically optimized) gates on a quantum processing unit and demonstrate that our algorithm effectively captures real time evolution.

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Sheng-Hsuan Lin, Rohit Dilip, Andrew G. Green, Adam Smith, Frank Pollmann. 2020-08-24. Real- and imaginary-time evolution with compressed quantum circuits. https://doi.org/10.1103/prxquantum.2.010342

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