Entanglement gap, corners, and symmetry breaking
- URL: http://arxiv.org/abs/2010.00787v2
- Date: Sun, 6 Dec 2020 20:06:07 GMT
- Title: Entanglement gap, corners, and symmetry breaking
- Authors: Vincenzo Alba
- Abstract summary: We investigate the finite-size scaling of the lowest entanglement gap $deltaxi$ in the ordered phase of the two-dimensional quantum spherical model (QSM)
The faster decay in the ordered phase reflects the presence of magnetic order.
In particular, we are able to compute the corner contribution to $Omega$, at least for the case of a square corner.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We investigate the finite-size scaling of the lowest entanglement gap
$\delta\xi$ in the ordered phase of the two-dimensional quantum spherical model
(QSM). The entanglement gap decays as $\delta\xi=\Omega/\sqrt{L\ln(L)}$. This
is in contrast with the purely logarithmic behaviour as
$\delta\xi=\pi^2/\ln(L)$ at the critical point. The faster decay in the ordered
phase reflects the presence of magnetic order. We analytically determine the
constant $\Omega$, which depends on the low-energy part of the model dispersion
and on the geometry of the bipartition. In particular, we are able to compute
the corner contribution to $\Omega$, at least for the case of a square corner.
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