Spectrum and correlation functions of a quasi-one-dimensional quantum Ising model.
For a model of weakly coupled quantum Ising chains we outline the phase diagram and establish that well below the transition line the system has a remarkably one-dimensional spectrum. We study the dynamical magnetic susceptibility and find a very rich spectrum with several modes corresponding to a fundamental particle and its bound states. The approach is based on the Bethe ansatz and the random phase approximation applied to the interchain exchange.
Carr
Sam T
ST
Department of Physics, Building 510A, Brookhaven National Laboratory, Upton, New York 11973, USA.
Tsvelik
Alexei M
AM