Eigenstate thermalization hypothesis in two-dimensional XXZ model with
or without SU(2) symmetry
- URL: http://arxiv.org/abs/2210.14589v1
- Date: Wed, 26 Oct 2022 10:00:44 GMT
- Title: Eigenstate thermalization hypothesis in two-dimensional XXZ model with
or without SU(2) symmetry
- Authors: Jae Dong Noh
- Abstract summary: We show that the eigenstate thermalization hypothesis is still valid within each subspace where the total spin is a good quantum number.
Numerical analysis of the Hamiltonian eigenvalue spectrum and matrix elements of an observable in the Hamiltonian eigenstate basis supports that the two-dimensional XXZ model follows the eigenstate thermalization hypothesis.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We investigate the eigenstate thermalization properties of the spin-1/2 XXZ
model in the two-dimensional rectangular lattices of size $L_1\times L_2$ under
the periodic boundary conditions. Exploiting the symmetry property, we can
perform the exact diagonalization study of the energy eigenvalues up to system
size $4\times 7$ and of the energy eigenstates up to $4\times 6$. Numerical
analysis of the Hamiltonian eigenvalue spectrum and matrix elements of an
observable in the Hamiltonian eigenstate basis supports that the
two-dimensional XXZ model follows the eigenstate thermalization hypothesis.
When the spin interaction is isotropic the XXZ model Hamiltonian conserves the
total spin and has the SU(2) symmetry. We show that the eigenstate
thermalization hypothesis is still valid within each subspace where the total
spin is a good quantum number.
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