Work

Spectral and entanglement properties of the random-exchange Heisenberg chain

Year: 2025

Type: article

Abstract: We study the many-body localization problem in the non-Abelian SU(2)-invariant random antiferromagnetic exchange model in 1D. Exact and sparse matrix diagonalization methods are used to calculate eigenvalues and eigenvectors of the Hamiltonian matrix. We investigate the behavior of the energy level gap-ratio statistic, participation ratio, entanglement entropy and the entanglement spectral parameter as a function of disorder strength. Different distributions of random couplings are considered. We find, up to L = 24 , a clear distinction between our non-Abelian model and the more often studied random field Heisenberg model: the regime of seemingly localized behavior is much less pronounced in the random exchange model than in the field model case.

Source: Physical review. B./Physical review. B

DOI: 10.1103/physrevb.111.104202

Authors: Yilun Gao, Rudolf A. Römer

Institution: University of Warwick

Language: English

Topic: Quantum many-body systems

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funder: Engineering and Physical Sciences Research Council

Award: Sulis: An EPSRC platform for ensemble computing delivered by HPC Midlands+