Bosonization in the two-channel Kondo model

The bosonization of the S=1/2 anisotropic two-channel Kondo model is shown to yield two equivalent representations of the original problem. In a straight-forward extension of the Emery-Kivelson approach, the interacting resonant level model previously derived by the Anderson-Yuval technique is obtained. In addition, however, a compactified ''(sigma,tau)'' description is also found. The strong coupling fixed point of the (sigma,tau) model was originally postulated to be related to the intermediate coupling fixed point of the two-channel Kondo model. The equivalence of the sigma,tau model to the two-channel Kondo model is formally established. A summary of what one may learn from a simple study of these different representations is also given.