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 $delta\xi=Omega/sqrt{Lln(L)}$. 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.
Entanglement gap, corners, and symmetry breaking
Vincenzo Alba
2020-01-01
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 $delta\xi=Omega/sqrt{Lln(L)}$. 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
