<POTENTIAL> coupled_recovery

This potential provides a slight modification on the gen_evp potential in that it couples the back stress effect in recovery. The kinematic variables are the only ones affected in this coupling. The evolution for each kinematic variable \(j\) will use the following form:

(455)\[\dot{\ten X}_j = \dot{\lambda}\ten m_j(\ten \sigma, \lambda, \ten X_j) - \dot{\ten \omega}_j(\ten X) \hskip2cm \ten X = \sum_i\ten X_i\]