Ground-state selection via nonlinear quantum dissipation
Abstract
Finding the ground state of complex quantum systems remains a central challenge in many-body physics, quantum chemistry, and combinatorial optimization, due to the exponential growth of the Hilbert-space dimension and the entangled structure of ground states. We show that quantum Landau--Lifshitz-Gilbert (QLLG) dynamics, proposed in [Phys. Rev. Lett. 133, 266704 (2024)], provides a physically realizable, real-time nonlinear mechanism that selectively suppresses excited-state components and drives the system toward the lowest-energy eigenstate contained in the initial state. Unlike purely numerical methods such as the imaginary-time projection method, QLLG combines coherent precession with dissipative suppression, enabling experimentally accessible ground-state preparation. For random initial states in the -qubit Hilbert space of dimension , convergence occurs in times scaling linearly with system size, , and inversely with the spectral gap. We provide numerical simulations of our analytical results with a Hamiltonian describing an interacting spin chain with Heisenberg exchange and a Zeeman term. Our results identify nonlinear quantum dissipation as a powerful tool for real-time ground-state preparation in large quantum systems and quantum optimization.
Cite
@article{arxiv.2604.03731,
title = {Ground-state selection via nonlinear quantum dissipation},
author = {Alireza Ataei and Olle Eriksson and Vahid Azimi Mousolou},
journal= {arXiv preprint arXiv:2604.03731},
year = {2026}
}