Clapping modes in unconventional superconductors

A. V. Balatsky, P. Kumar, J. R. Schrieffer

We consider a superconducting state with a mixed symmetry order parameter components, e.g. $d+is$ or $d+i{d}^{\prime }$ with $d^{\prime }=d_{xy}$. We argue for the existence of the new orbital magnet…