Solitonic integrable perturbations of conformal field theories

The construction of new series of integrable quantum field theories whose equations-of-motion are related to the non-abelian affine Toda equations is summarized. All these theories can be thought of as generalizations of the sine-Gordon theory. They admit (charged) soliton solutions, exhibit a mass-gap, and are described by a unitary (real positive-definite) action. Their quantum integrability and semi-classical spectrum of solitons are also discussed.