超导电性
We characterize the superconducting diode effect (SDE) in two-dimensional diffusive structures with Rashba spin-orbit coupling using the quasiclassical formalism. We consider both homogeneous superconductors and Josephson junctions. In the…
We consider the effect of the nematic order on the formation of the superconducting state in iron pnictides and chalcogenides. Nematic order with the $B_{2g}$ symmetry is modelled as the $d$-type Pomeranchuk instability and treated within…
Recent advancements in the realizations of superconducting diodes have pushed the diode coefficient $\eta$ towards its theoretical maximum of $\eta=1$. In this work, we describe the construction of logic gates NOT, AND, OR, NAND and NOR…
The physics of superconductivity in magic-angle twisted bilayer graphene (MATBG) is a topic of keen interest in moir\'e systems research, and it may provide insight into the pairing mechanism of other strongly correlated materials such as…
A recent experimental study announced the emergence of superconductivity in La$_3$Ni$_2$O$_7$ under pressure, with the highest observed superconducting transition temperature ($T_c$) reaching approximately 80 K beyond 14 GPa. While…
The interplay between electron-electron interactions and weak localization (or anti-localization) phenomena in two-dimensional systems can significantly enhance the superconducting transition temperature. We develop the theory of quantum…
The simultaneous presence of polarity and metallicity in a material signifies an exotic polar metal state, but such materials are extremely rare, especially in bulk form, due to mutually exclusive nature of the fundamental defining…
We present a study of the Berezinskii-Kosterlitz-Thouless (BKT) transition in mildly disordered NbN nanoporous (NP) films. The measured superfluid stiffness, Js, is found to be much lower than that predicted by considering the reduction in…
The current-phase relation for a ballistic SNS junction in a 1D wire at T = 0 was derived by Thuneberg [1] neglecting phase gradients in superconducting leads. This invalidates the derivation, since the charge conservation law is violated.…
Superconductor/ferromagnet/superconductor Josephson junctions with anomalous phase shift $\varphi_0$ ($\varphi_0$-S/F/S JJs) implement a coupling between the superconducting phase and the spin degrees of freedom. Here we investigate the…
Superconductivity and magnetism are competing effects that can coexist in certain regimes. Their co-existence leads to unexpected new behaviors that include the onset of exotic electron pair mechanisms and topological phases. In this work,…
The quasiparticle scattering interference (QSI) is intimately related to the nature of the quasiparticle and of its interplay with a variety of electronic orders and superconductivity. Here starting from the microscopic octet scattering…
High critical current density Jc is generally the most important property of any superconductor used for applications. The critical current Ic is most frequently measured by transport 4 probe V-I techniques and the measured Ic is then…
Two-dimensional Janus transition-metal chalcogenide -hydrides (2D-JTMCs) feature a three layered structure, with a central layer of transition metal atoms, with chalcogenides below and hydogens above. This asymmetry endows 2D-JTMCs with…
Without applied bias voltage, a superconducting phase difference can drive a charge Josephson supercurrent in a superconductor junction. In analogy, we here theoretically propose a spin phase that intrinsically generates spin Josephson…
We investigate the Andreev reflection in a normal metal/charge-4e superconductor junction.Compare with the electron-hole conversion in normal charge-2e superconductors, here four electrons participate simultaneously, enriching the…
The combination of spin-orbit coupling and superconductivity induces unconventional spin-triplet correlation in Ising superconductors. We theoretically investigate the spin transport through a normal metal-Ising superconductor junction,…
Superconductivity and Bloch band Berry curvature responses represent two distinct paradigms of quantum coherent phenomena. The former relies on the collective motion of a many-body state while the latter proceeds from the momentum-space…
At a superconductor-ferromagnet (S/F) interface, the F layer can introduce a magnetic exchange field within the S layer, which acts to locally spin split the superconducting density of states. The effect of magnetic exchange fields on…
Symmetry plays an important role in determining the physical properties in condensed matter physics, as the symmetry operations of any physical property must include the symmetry operations of the point group of the crystal. As a…