## Feshbach-type resonances for two-particle scattering in graphene    [PDF]

C. Gaul, F. Domínguez-Adame, F. Sols, I. Zapata
Two-particle scattering in graphene is a multi-channel problem where the energies of the identical or opposite helicity channels lie in disjoint energy segments. Due to the absence of Galilean invariance, these segments depend on the total momentum $Q$. We solve the scattering problem for a model s-wave separable potential. The scattering amplitudes show three Feshbach-type resonances in the identical-helicity channel due to virtual transitions to the closed opposite-helicity channel. In the limit $Q \rightarrow 0$, one of the resonances survives and the opposite-helicity scattering amplitudes vanish.
View original: http://arxiv.org/abs/1307.4615