Finite-size spectrum of the staggered six-vertex model with antidiagonal boundary conditions

Abstract

The finite-size spectrum of the critical staggered six-vertex model with antidiagonal boundary conditions is studied. Similar to the case of periodic boundary conditions, we identify three different phases. In two of those, the underlying conformal field theory can be identified to be related to the twisted $U(1)$ Kac-Moody algebra. In contrast, the finite size scaling in the third regime, whose critical behaviour with the (quasi-)periodic BCs is related to the 2d black hole CFTs possessing a non-compact degree of freedom, is more subtle. Here with antidiagonal BCs imposed, the corrections to the scaling of the ground state grow logarithmically with the system size, while the energy gaps appear to close logarithmically. Moreover, we obtain an explicit formula for the Q-operator which is useful for numerical implementation.

21 pages

References in corpus (5)

• The XXZ model with anti-periodic twisted boundary conditions
• Phase Diagram of an Integrable Alternating $U_q[sl(2|1)]$ Superspin Chain
• Lattice regularisation of a non-compact boundary conformal field theory
• Integrable boundary conditions for staggered vertex models
• On the scaling behaviour of an integrable spin chain with ${\mathcal{Z}}_r$ symmetry

Cited by in corpus (1)

• Quantum-group-invariant $D_{n+1}^{(2)}$ models: Bethe ansatz and finite-size spectrum