Related papers: Impurity Knight shift in quantum dot Josephson jun…
The superconducting state of Sr$_2$RuO$_4$ was once thought to be a leading candidate for $p$-wave superconductivity. A constant Knight shift below the transition temperature provided evidence for spin-triplet pairing, and a $\pi$ phase…
The Zeeman splitting of localized electrons in a quantum dot in the Kondo regime is studied using a new slave-boson formulation. Our results show that the Kondo peak splitting depends on the gate potential applied to the quantum dot and on…
An odd-occupied quantum dot in a Josephson junction can flip transmission phase, creating a {\pi}-junction. When the junction couples topological superconductors, no phase flip is expected. We investigate this and related effects in a…
We consider a model of a Josephson junction of two topological superconducting wires mediated by an interacting quantum dot. An additional normal electrode coupled to the dot from the top allows to probe its density of states. The Majorana…
We investigate the Josephson coupling between two superconductors mediated through an infinite U Anderson impurity, adapting a variational wavefunction approach which has proved successful for the Kondo model. Unlike the Kondo problem,…
We use a hybrid superconductor-semiconductor transmon device to perform spectroscopy of a quantum dot Josephson junction tuned to be in a spin-1/2 ground state with an unpaired quasiparticle. Due to spin-orbit coupling, we resolve two…
$\mathbb{Z}_4$ parafermions can be realized in a strongly interacting quantum spin Hall Josephson junction or in a spin Hall Josephson junction strongly coupled to an impurity spin. In this paper we study a system that has both features,…
We investigate the Josephson current J(\phi) through a quantum dot embedded between two superconductors showing a phase difference \phi. The system is modeled as a single Anderson impurity coupled to BCS leads, and the functional and the…
We investigate theoretically the Josephson junction of semiconductor nanowire with strong spin-orbit (SO) interaction in the presence of magnetic field. By using a tight-binding model, the energy levels $E_n$ of Andreev bound states are…
We investigate the supercurrent through a quantum dot for the whole range of couplings using the numerical renormalization group method. We find that the Josephson current switches abruptly from a $\pi$- to a 0-phase as the coupling…
We present a theoretical study of the effect of spin-filtering on the Josephson and dissipative quasiparticle currents in a superconducting tunnel junction. By combining the quasiclassical Green's functions and the tunneling Hamiltonian…
We analyze nonperturbatively the behavior of a Josephson junction in which two BCS superconductors are coupled through an Anderson impurity. We recover earlier perturbative results which found that a $\delta=\pi$ phase difference is…
We study the Josephson junction mediated by the quantum spin Hall edge states and show that electron-electron interactions lead to a dissipationless fractional Josephson effect in the presence of time-reversal symmetry. Surprisingly, the…
Recent nuclear magnetic resonance studies [A. Pustogow {\it et al.}, arXiv:1904.00047] have challenged the prevalent chiral triplet pairing scenario proposed for Sr$_2$RuO$_4$. To provide guidance from microscopic theory as to which other…
We theoretically study the superconducting proximity effect in a quantum dot coupled to two superconducting leads when the intradot interaction between electrons is made attractive. Because of the superconducting proximity effect, the…
A model of a ladder of Josephson junctions in a magnetic field is considered. The topological features of the zero-temperature phase diagram, as a function of charging energy and small deviations from commensurability of the vortex lattice,…
We consider the hyperfine-mediated transition rate between Zeeman split spin states of the lowest orbital level in a GaAs quantum dot. We separate the hyperfine Hamiltonian into a part which is diagonal in the orbital states and another one…
We investigate the switching current distributions of ferromagnetic anomalous Josephson junctions subjected to a linearly increasing bias current. Our study uncovers a significant correlation between the position of the switching current…
A superconductor/ferromagnet/superconductor Josephson junction with anomalous phase shift (phi_0-S/F/S JJ) is a system, where the anomalous ground state shift phi_0 provides a direct magnetoelectric coupling between a magnetic moment and a…
We consider ballistic SQUIDs with spin filtering inside half-metallic ferromagnetic arms. A singlet Cooper pair cannot pass through an arm in this case, so the Josephson current is entirely due to the Cooper pair splitting, with two…