Related papers: Interaction between Kondo impurities in a quantum …
The influence of impurities, embedded into the isolating spacer (I) between two ferromagnetic electrodes (F), on the I-V curve and tunnel magnetoresistance (TMR), is theoretically investigated. It is shown, that the current and TMR are…
We investigate different methods to compute the DC conductance in a quantum wire doped with some impuritied by exploiting the integrability of the theories under consideration. As an essential ingredient in all methods we evaluate the…
Paramagnetic impurities in a quantum spin-liquid can result in Kondo effects with highly unusual properties. We have studied the effect of locally exchange-coupling a paramagnetic impurity with the spin-1/2 honeycomb Kitaev model in its…
Geometrically frustrated quantum impurities coupled to metallic leads have been shown to exhibit rich behavior with a quantum phase transition separating Kondo screened and local moment phases. Frustration in the quantum impurity can…
The Kondo problem, for a quantum dot (QD), subjected to an external bias, is analyzed in the limit of infinite Coulomb repulsion by using a consistent equations of motion method based on a slave-boson Hamiltonian. Utilizing a strict…
We study analytically a system made up of a quantum ring with a dipolar impurity and under the effect of an Aharonov-Bohm field. We calculate the exact values of the energies and we also get the exact expressions of the wave functions.
We study how the formation of the Kondo compensation cloud influences the dynamical properties of a magnetic impurity that tunnels between two positions in a metal. The Kondo effect dynamically generates a strong tunneling…
Two electronic channels competing to screen a single impurity spin, as in the two-channel Kondo model, are expected to generate a ground state with nontrivial entanglement structure. We exploit a spin-chain representation of the two-channel…
Quantum impurity problems in Tomonaga-Luttinger liquids (TLLs) are reviewed with emphasis on their analogy to the Kondo problem in Fermi liquids. First, the problem of a static impurity in a spinless TLL is considered, which is related to…
The conduction electron density of states nearby single magnetic impurities, as measured recently by scanning tunneling microscopy (STM), is calculated, taking into account tunneling into conduction electron states only. The Kondo effect…
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…
In his renormalization paper of the Kondo effect Wilson replaced the full band of s-electrons by a small number of ''Wilson states''. He started from a rather artificial symmetric band with constant density of states and constant…
The effect of a magnetic (S=1/2) impurity coupled to a 2D system of correlated electrons (described by the t--J model) is studied by exact diagonalisations. It is found that, if the exchange coupling of the impurity with the neighboring…
We investigate the mutual influence of impurities in two-dimensional d-wave superconductors involving self-consistent solutions of the Bogoliubov-de Gennes equations. The local order parameter suppression, the local density of states (LDOS)…
The impurity effects on the quantum coherence of a few-boson system are studied within the two-site Hubbard model. Periodical collapses and revivals of coherence occur in the presence of either polarized or unpolarized fermionic impurities.…
We study the low-temperature thermodynamics of a spin-S magnetic impurity coupled to m degenerate bands of interacting electrons in one dimension. By exploiting boundary conformal field theory techniques, we derive exact results for the…
We study transport through a one-dimensional quantum wire of correlated fermions connected to semi-infinite leads. The wire contains either a single impurity or two barriers, the latter allowing for resonant tunneling. In the leads the…
The influence on the I-V characteristics and tunnel magnetoresistance (TMR), of impurities embedded into the insulating barrier I separating the two ferromagnetic electrodes F of a magnetic tunnel junction, was theoretically investigated.…
The nonlinear conductance of a one-dimensional quantum wire adiabatically coupled to Fermi Liquid electron reservoirs is determined in presence of an impurity. We show that electron-electron interaction in connection with the finite length…
We discuss the effect of multichannel Kondo impurities on superconductivity. In the strong coupling regime such impurities are pairbreakers, in contrast to the ordinary Kondo effect. Measurements of $T_c$-suppression may help in identifying…