Related papers: Equilibrium spin current through the tunnelling ju…
We consider the problem of tunneling between two leads via a localized spin 1/2 or any other microscopic system which can be modeled by a two-level Hamiltonian. We assume that a constant magnetic field ${\bf B}_0$ acts on the spin, that…
Superconducting systems that simultaneously lack space-inversion and time-reversal symmetries have recently been the subject of a flurry of experimental and theoretical research activities. Their ability to carry supercurrents with…
We use the Gross-Pitaevskii equation to study Josephson tunneling between two weakly coupled Bose-Einstein condensates, which compose spin-1 bosons. We show that a rotating magnetic field on one side can produce a phase difference across…
We study tunneling conductance in ferromagnetic semiconductor/insulator/s-wave superconductor junction where Rashba spin-orbit interaction (RSOI) and exchange field are taken into account in the ferromagnetic semiconductor. We show that…
We examine cross-correlations (CCs) in the tunneling currents through two parallel interacting quantum dots coupled to four independent ferromagnetic electrodes. We find that when either one of the two circuits is in the parallel…
We investigate theoretically the spin transport in two-terminal mesoscopic rings in the presence of both the Rashba spin-orbit interaction (RSOI) and the Dresselhaus spin-orbit interaction (DSOI). We find that the interplay between the RSOI…
We predict that unpolarized charge current driven through the longitudinal leads attached to ballistic quantum-coherent two-dimensional electron gas (2DEG) in semiconductor heterostructure will induce a {\em pure} spin current, which is not…
In order to enhance spin injection efficiency from ferromagnetic (FM) metal into a two-dimensional electron gas (2DEG), we introduce another FM metal and two tunnel barriers (I) between them to investigate the current polarization in such…
A system exhibiting multiple simultaneously broken symmetries offers the opportunity to influence physical phenomena such as tunneling currents by means of external control parameters. Time-reversal symmetry and inversion symmetry are both…
The ideal diode is a theoretical concept that completely conducts the electric current under forward bias without any loss and that behaves like a perfect insulator under reverse bias. However, real diodes have a junction barrier that…
Using the Keldysh formalism the tunneling current through a hybrid structure where a confined magnetic insulator (I) is sandwiched between two non-magnetic leads is calculated. The leads can be either normal metals (M) or superconductors…
We analyze the charge and spin dynamics in a DC biased double quantum dot driven by crossed DC and AC magnetic fields. In this configuration, spatial delocalization due to inter-dot tunnel competes with intra-dot spin rotations induced by…
We theoretically study the spin-dependent transport in a ferromagnet/super- conductor/ferromagnet double tunnel junction. The tunneling current in the antiferromagnetic alignment of the magnetizations gives rise to a spin imbalance in the…
We develop a theory for charge and spin current between two canted magnetic leads flowing through a quantum dot with an arbitrary local interaction. For a noncollinear magnetic configuration, we calculate equilibrium and nonequilibrium…
Based on Keldysh non-equilibrium Green function method, we have investigated spin current production in a hybrid T-shaped device, consisting of a central quantum dot connected to the leads and a side dot which only couples to the central…
The supercurrent diode effect (SDE), characterized by unequal critical currents in opposite directions, has been observed with or without magnetic fields, yet mechanisms enabling zero-field SDE without explicit symmetry breaking remain…
We theoretically study the spin current between two polarized Fermi gases with repulsive interactions near the itinerant ferromagnetic phase transition. We consider a two-terminal model where the left reservoir is fixed to be fully…
We derive an expression for the spin-current through a tunnel barrier in terms of many-body Green's functions. The spin current has two contributions. One can be associated with angular-momentum transfer by spin-polarized charge currents…
A scanning tunneling microscope can probe the inelastic spin excitations of a single magnetic atom in a surface via spin-flip assisted tunneling in which transport electrons exchange spin and energy with the atomic spin. If the inelastic…
In this work, we calculate with ab initio methods the current-voltage characteristics for ideal single- and double-barrier Fe/MgO (001) magnetic tunnel junctions. The current is calculated in the phase-coherent limit by using the recently…