Boundary bound states in the SUSY sine-Gordon model with Dirichlet boundary conditions

Abstract: We analyze the ground state structure of the supersymmetric sine-Gordon model via the lattice regularization. The nonlinear integral equations are derived for any values of the boundary parameters by the analytic continuation and showed three different forms depending on the boundary parameters. We discuss the state that each set of the nonlinear integral equations characterizes in the absence of source terms. Four different pictures of the ground state are found by numerically studying the positions of zeros in the auxiliary functions. We suggest the existence of two classes in the SUSY sine-Gordon model, which cannot be mixed each other.