Quantum effects in rotationally invariant spin glass models

Yoshinori Hara; Yoshiyuki Kabashima

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arXiv · 2504.18034

Quantum effects in rotationally invariant spin glass models

Yoshinori Hara·Yoshiyuki Kabashima

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Abstract

This study investigates the quantum effects in transverse-field Ising spin glass models with rotationally invariant random interactions. The primary aim is to evaluate the validity of a quasi-static approximation that captures the imaginary-time dependence of the order parameters beyond the conventional static approximation. Using the replica method combined with the Suzuki--Trotter decomposition, we established a stability condition for the replica symmetric solution, which is analogous to the de Almeida--Thouless criterion. Numerical analysis of the Sherrington--Kirkpatrick model estimates a value of the critical transverse field, $Γ_\mathrm{c}$, which agrees with previous Monte Carlo-based estimations. For the Hopfield model, it provides an estimate of $Γ_\mathrm{c}$, which has not been previously evaluated. For the random orthogonal model, our analysis suggests that quantum effects alter the random first-order transition scenario in the low-temperature limit. This study supports a quasi-static treatment for analyzing quantum spin glasses and may offer useful insights into the analysis of quantum optimization algorithms.

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Yoshinori Hara, Yoshiyuki Kabashima. 2025-10-09. Quantum effects in rotationally invariant spin glass models. https://arxiv.org/abs/2504.18034

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