The signature of inhomogeneous superconductivity

I contributed to this work during my time as an undergraduate at Clark University. This work describes the RF magnetic response of organic superconductors at low temperature and high magnetic field, where the field is applied parallel to the quasi-2D superconducting layers of the organic crystal. Under certain conditions, these materials are thought to host an unconventional phase known as the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase, in which Cooper pairs acquire a finite center of mass momentum leading to a spatially modulated superconducting order parameter.

Abstract: Superconductivity can be inhomogeneous, having a periodically modulated order parameter, in materials that have long electronic mean free paths and where the effects of vortices are suppressed. One class of materials that has these properties is crystalline organic superconductors. They are stoichiometric compounds and highly anisotropic crystals such that the vortices that form can hide in the least conducting layers. We analyze recent data to look for complexity in the inhomogeneous states, such as changes in the order parameter nodal structure.