Superconductivity
Recent experiments observed a phase transition within the superconducting regime of the heavy-fermion system CeRh$_2$As$_2$ when subjected to a $c$-axis magnetic field. This phase transition has been interpreted as a parity switching from…
Based on a recently developed framework, we conduct classifications of time-reversal symmetric topological superconductors with conventional pairing symmetries. Our real-space approach clarifies the nature of boundary modes in nontrivial…
We calculate the effects of carrier-density structuration and patterning on thin films of the cuprate superconductor La$_{2-x}$Sr$_{x}$CuO$_{4}$, in order to optimize its functional characteristics as sensing material for resistive…
Ternary hydrides are considered as the ideal candidates with high critical temperature (Tc) stabilized at submegabar pressure, evidenced by the recent discoveries in LaBeH8 (110 K at 80 GPa) and LaB2H8 (106 K at 90 GPa). Here, we…
The experimental realisation of unconventional superconductivity and charge order in kagome systems \textit{A}V$_3$Sb$_5$ is of critical importance. We conducted a highly systematic study of Cs(V$_{1-x}$Nb$_x$)$_3$Sb$_5$ with $x$=0.07…
Jorge Hirsch, in his Comment on my article published in Entropy, agrees that the conventional BCS theory of superconductivity contradicts the second law of thermodynamics. He tries to prove that this theory cannot be valid because of this…
The newly discovered family of titanium-based kagome metals, ATi$_{3}$Bi$_{5}$ (where A can be Rb or Cs), has been found to exhibit non-trivial band topology and fascinating electronic instabilities, including electronic nematicity and…
The low-energy quasiparticle states in the mixed state of most superconductors remain Bloch waves due to the presence of supercurrent around vortex cores. In contrast, the Weyl superconductor (WSC) may display Dirac-Landau levels in the…
Josephson scanning tunneling microscopy (JSTM) is a powerful probe of the local superconducting order parameter, but studies have been largely limited to cases where superconducting sample and superconducting tip both have the same gap…
Topological superconductors have garnered significant attention due to their potential for realizing topological quantum computation. However, a universal computational tool based on first-principles calculations for predicting topological…
Scanning tunneling microscopy (STM) is perhaps the most promising way to detect the superconducting gap size and structure in the canonical unconventional superconductor Sr$_2$RuO$_4$ directly. However, in many cases, researchers have…
We study the Josephson effect in a superconductor/altermagnet/superconductor (S/AM/S) junction. We find anomalous phenomena including $0$-$\pi$ transition as well as multi-nodal current-phase relations. Similar to $d$-wave superconductor,…
The Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, an unusual superconducting state, defies high magnetic fields beyond the Pauli paramagnetic limit. It exhibits a spatial modulation of the superconducting order parameter in real space and…
Using the Sierpinski gasket (triangle) and carpet (square) lattices as examples, we theoretically study the properties of fractal superconductors. For that, we focus on the phenomenon of $s$-wave superconductivity in the Hubbard model with…
The kagome lattice is very attractive as it can host many novel quantum states, such as the charge density wave, superconductivity, quantum spin liquid, etc. Meanwhile, iridates often exhibit a strong spin-orbit coupling (SOC) effect due to…
The complex conductivity of underdoped and optimally doped YBa$_2$Cu$_3$O$_{7-\delta}$ samples and overdoped similar compound Y$_{0.7}$Ca$_{0.3}$Ba$_2$Cu$_3$O$_{7-\delta}$ was measured using time-domain terahertz spectroscopy. In the normal…
We study the coexistence of superconductivity (SC) and density-wave state and reconcile various puzzling experimental data in organic superconductors (TMTSF)$_{2}$PF$_{6}$ and (TMTSF)$_{2}$ClO$_{4}$. The anisotropic resistance drop above…
The hybrid ferromagnet-superconductor heterostructures have attracted extensive attention as they potentially host topological superconductivity. Relevant experimental signatures have recently been reported in CrBr3/NbSe2…
The notion of topological order (TO) can be defined through the characteristic ground state degeneracy of a system placed on a manifold with non-zero genus $g$, such as a torus. This ground state degeneracy has served as a key tool for…
The damage and the critical current density (Jc) degradation of polycrystalline superconductors induced by strain dramatically influence their performance in applications. Unfortunately, the state-of-the-art experimental techniques are…