Related papers: Quantum phase transition in a minimal model for th…
The Kondo effect in coupled quantum dots is investigated from the viewpoint of transmission spectroscopy using the slave-boson formalism of the Anderson model. The antiferromagnetic spin-spin coupling $J$ between the dots is taken into…
We investigate the Josephson effect through a molecular quantum dot magnet connected to superconducting leads. The molecule contains a magnetic atom, whose spin is assumed to be isotropic. It is coupled to the electron spin on the dot via…
We show how the superconducting phase difference in a Josephson junction may be used to split the Kramers degeneracy of its energy levels and to remove all the properties associated with time reversal symmetry. The superconducting phase…
We study a superconducting quantum point contact made of a narrow In$_{0.75}% $Ga$_{0.25}$As channel with Nb proximity electrodes. The narrow channel is formed in a gate-fitted constriction of InGaAs/InAlAs/InP heterostructure hosting a…
Topology, symmetry, electron correlations, and the interplay between them have formed the cornerstone of our understanding of quantum materials in recent years and are used to identify new emerging phases. While the first two give a fair…
In this work, we manipulate the phase shift of a Josephson junction using a parallel double quantum dot (QD). By employing a superconducting quantum interference device, we determine how orbital hybridization and detuning affect the…
We investigate the boundary phenomena that arise in a finite-size $XX$ spin chain interacting through an $XX$ interaction with a spin$-\frac{1}{2}$ impurity located at its edge. Upon Jordan-Wigner transformation, the model is described by a…
The current-phase relation (CPR) for a short Josephson junction placed in the nonuniform field of a small ferromagnetic particle is studied. The effect of the particle produced on the junction appears to be strong due to the formation of…
In the Josephson effect, coherent Cooper pair tunneling is driven by the phase difference between the superconducting order parameters on opposite sides of the junction. By analogy, differences in order parameters across a junction should…
The inherent complexity of system-bath interactions often requires making critical approximations, which we here show to have a radical influence on the renormalization group flow and the resulting phase diagram. Specifically, for the…
Topological superconductivity holds promise for fault-tolerant quantum computing. While planar Josephson junctions are attractive candidates to realize this exotic state, direct phase-measurements as the fingerprint of the topological…
In analogy to conventional semiconductor diodes, the Josephson diode exhibits superconducting properties that are asymmetric in applied bias. The effect has been investigated in number of systems recently, and requires a combination of…
We present a real-time diagrammatic theory for transport through interacting quantum dots tunnel coupled to normal and superconducting leads. Our formulation describes both the equilibrium and non-equilibrium superconducting proximity…
We consider a two-orbital impurity system with intra and inter-level Coulomb repulsion that is coupled to a single conduction channel. This situation can generically occur in multilevel quantum dots or in systems of coupled quantum dots.…
Quantum impurity models are the prototypical examples of quantum many-body dynamics which manifests in their spectral and transport properties. Single channel Anderson(and Kondo model) leads to the Fermi liquid ground state in the strong…
We tune the barrier of a Josephson junction through a zero-temperature metal-insulator transition and study the thermodynamic behavior of the junction in the proximity of the quantum-critical point. We examine a short-coherence-length…
Tunneling conductance through two quantum dots, which are connected in series to left and right leads, is calculated by using the numerical renormalization group method. As the hopping between the dots increases from very small value, the…
We discuss correlated lattice models with a time-dependent potential across a barrier and show how to implement a Josephson-junction-like behavior. The pairing occurs by a correlation effect enhanced by the symmetry of the system. In order…
We demonstrate the Josephson effect in a serial double quantum dot defined in a nanowire with epitaxial superconducting leads. The supercurrent stability diagram adopts a honeycomb pattern with electron-hole and left-right reflection…
We study two quantum dots embedded in the arms of an Aharonov-Bohm ring threaded by a magnetic flux. The system can be described by an effective one-impurity Anderson model with an energy- and flux-dependent density of states. For specific…