title: Collective mode in a superconductor with mixed-symmetry order parameter components
abstract: We consider a superconducting state with mixed-symmetry order parameter components, e.g., d+is or d+id(') with d(') = d(xy). We argue for the existence of a new orbital magnetization mode which corresponds to oscillations of relative phase straight phi between two components around an equilibrium value of straight phi = pi / 2. It is similar to the "clapping" mode in superfluid 3He-A. We estimate the frequency of this mode omega(0)(B,T) depending on the field and temperature for the specific case of magnetic field induced d(') = d(xy) state. This mode is tunable with a magnetic field with omega(0)(B,T) approximately BDelta(0), where Delta(0) is the magnitude of the d-wave order parameter. We also estimate the velocity s(B,T) of this mode.
authors.affiliation: Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.initials: AV
authors.lastname: Balatsky
authors.initials: P
authors.lastname: Kumar
authors.initials: JR
authors.lastname: Schrieffer