Comunicazione
Magneto-topological transitions and current states in multicomponent superconductors.
Yerin Y., Drechsler S.-L., Cuoco M., Petrillo C.
Multicomponent superconductors can host different nonstandard phenomena, such as broken-time reversal symmetry states (BTRS), exotic Fulde-Ferrell-Larkin-Ovchinnikov phases, etc. We show that in the case of a two-component superconducting quasi-one-dimensional channel this catalogue can be extended by a novel inhomogeneous current state, which we have termed as a multiple-momenta state or, in short, a $multiple-q$ state, characterized by the coexistence of two different interpenetrating Cooper pair condensates with different total momenta. Within the Ginzburg-Landau formalism for a dirty two-band superconductor we reveal that under certain conditions, the occurrence of $multiple-q$ states can induce a cascade of transitions involving switching between them and the homogeneous BTRS (non-BTRS) states and vice versa leading this way to a complex interplay of homogeneous and inhomogeneous current states. We demonstrate that the modification of the kinetic energy of superconducting electrons in a doubly connected superconducting cylinder, determined by the applied flux, generally drives transitions from chiral superconducting states to configurations that are time-reversal symmetric.