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arXiv · 2608.30363

Quantum Imaginary Time Evolution on an Infinite 1D Chain

Hao-Ti Hung·Tung Tsao·Ying-Jer Kao
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Abstract

We introduce a quantum-circuit algorithm for performing imaginary-time evolution on infinite one-dimensional lattice systems. The method uses a parameterized quantum circuit to represent a uniform matrix product state ansatz. We derive the ITE algorithm using the time-dependent variational principle and employ the quantum Lanczos algorithm to improve the ground-state energy estimate. As a benchmark, we simulate the transverse-field Ising model using both classical simulators and IBM Quantum devices. Our analysis includes a statistical study of the distributions of the cost function and energy density obtained from quantum measurements, illustrating the effects of finite-sampling noise on convergence.

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Hao-Ti Hung, Tung Tsao, Ying-Jer Kao. 2026-08-31. Quantum Imaginary Time Evolution on an Infinite 1D Chain. https://arxiv.org/abs/2608.30363

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