Related papers: Superconductivity without inversion and time-rever…
Superconductors that spontaneously break time-reversal symmetry host complex order parameters and are widely regarded as a hallmark of unconventional superconductivity. Whether such symmetry breaking can also arise in superconductors with…
We consider the vestigial phase with broken time-reversal symmetry above the superconducting transition temperature of a two-component superconductor in two spatial dimensions. We show that, in contrast to 3D, a vestigial phase is in…
We study surface states of topological crystalline insulators and superconductors protected by inversion symmetry. These fall into the category of "higher-order" topological insulators and superconductors which possess surface states that…
Superconductivity in the two-dimensional (2D) limit is a fertile ground for exotic quantum phenomena-many of which remain elusive in their 3D counterparts. While studies of 2D superconductivity have predominantly focused on mono- or…
A novel time-reversal symmetry breaking state is found theoretically in the Josephson junction between the two-gap superconductor and the conventional s-wave superconductor. This occurs due to the frustration between the three order…
The structure of superconducting order parameter near the surface of a two-band superconductor with $s_{\pm}$ order parameter in the bulk is theoretically investigated. The main parameter of the surface, which determines the appropriate…
Two-dimensional (2D) superconductors, characterized by their inherent quantum confinement, strong spin-orbit coupling, and diverse forms of symmetry breaking, provide an ideal platform for exploring novel quantum transport phenomena. This…
We show that a two-dimensional semiconductor with Rashba spin-orbit coupling could be driven into the second-order topological superconducting phase when a mixed-pairing state is introduced. The superconducting order we consider involves…
In the absence of time-reversal invariance, metals without inversion symmetry may exhibit nonreciprocal charge transport -- a magnetochiral anisotropy that manifests as unequal electrical resistance for opposite current flow directions. If…
Time-reversal-symmetry breaking is generally understood to be detrimental for superconductivity. However, recent experiments found superconductivity emerging out of a normal state showing a finite anomalous Hall effect, indicative of…
We construct time reversal invariant topological superconductors and superfluids in two and three dimensions which are analogous to the recently discovered quantum spin Hall and three-d $Z_2$ topological insulators respectively. These…
Eigenstate multifractality is a distinctive feature of non-interacting disordered metals close to a metal-insulator transition, whose properties are expected to extend to superconductivity. While multifractality in three dimensions (3D)…
Non-reciprocal critical currents without applying an external magnetic field have been observed recently in several superconductors, in various forms of Graphene, a Kagome compound and in an under-doped cuprate. A necessary requirement for…
We consider different effects that arise when time-reversal symmetry breaking superconductors are subjected to an external magnetic field, thus rendering the superconductor to be in the mixed state. We focus in particular on two…
We investigate the physical mechanisms for achieving an electrical control of conventional spin-singlet superconductivity in thin films by focusing on the role of surface orbital polarization. Assuming a multi-orbital description of the…
Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional superconductors. When two superconducting gap functions with different symmetries compete, the relative phase channel…
We introduce a spinful variant of the Sachdev-Ye-Kitaev model with an effective time reversal symmetry, which can be solved exactly in the limit of a large number $N$ of degrees of freedom. At low temperature, its phase diagram includes a…
Symmetries have a crucial role in today's physics. In this thesis, we are mostly concerned with time reversal invariance (T-symmetry). A physical system is time reversal invariant if its underlying laws are not sensitive to the direction of…
There have been numerous studies on topological superconductivity in magnetic atomic chains deposited on s-wave superconductors. Most of these investigations have focused on spin-orbit interactions or helical spin orders. In this paper, we…
When a Mott metal-insulator transition is inhibited by a small amount of disorder in the layered dichalcogenide 1T-TaS$_2$, an inhomogeneous superconducting state arises below T=2.1 K, and coexists with a nearly-commensurate…