Lax Pair for the Free‐Fermion Eight‐Vertex Model

摘要

An explicit result on the quantum Lax pair for the eight‐vertex free‐fermion model with external fields in both directions is exhibited. Its relation to the quantum spectral transform and its corresponding Hamiltonian—theXYmodel with a transverse field—is discussed. The Yang‐Baxter relation is computed, and the equations of motion a