Related papers: Two-channel Kondo problem in coupled interacting h…
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…
We investigate the entanglement properties of a Kondo system undergoing a transition to a state with a quenched magnetic impurity, using the density matrix renormalization group (DMRG) method. We focus on a two-channel spin-1 Kondo impurity…
We discuss the conductance of a Luttinger liquid interrupted by a quantum dot containing a single resonant level. Using bosonisation and re-fermionisation methods, we find a mapping to a Kondo-type problem which possesses a non-trivial…
We discuss the physics of a of a spin-1 quantum dot, coupled to two metallic leads and develop a simple model for the temperature dependence of its conductance. Such quantum dots are described by a two-channel Kondo model with asymmetric…
We show that multiple point contacts on a barrier separating two laterally coupled quantum Hall fluids induce Aharonov-Bohm (AB) oscillations in the tunneling conductance. These quantum coherence effects provide new evidence for the…
We consider a magnetic impurity which interacts by hybridization with a system of weakly correlated electrons and determine the energy of the ground state by means of an 1/N_f expansion. The correlations among the conduction electrons are…
We illustrate the emergence of the three-channel Kondo effect in a seven-orbital impurity Anderson model hybridized with $\Gamma_7$ and $\Gamma_8$ conduction electron bands employing a numerical renormalization group method. In particular,…
We propose a predictive standard model for heavy electron systems based on a detailed phenomenological two-fluid description of existing experimental data. It leads to a new phase diagram that replaces the Doniach picture, describes the…
The Kondo cloud, represented by the correlations between the magnetic moment and the spin density in the leads of a Kondo setup, is until now eluding its observation. We exploit the unique coupling of spin and direction of motion of the…
It has been claimed that an impurity hopping between two sites in a metal can lead to non--Fermi liquid behavior if the bias between the two sites is tuned to zero. Here it is shown that several extra tunnelling processes are allowed; those…
A detailed study of the low-temperature physics of an interacting double quantum dot system in a T-shape configuration is presented. Each quantum dot is modeled by a single Anderson impurity and we include an inter-dot electron-electron…
We study a model proposed recently in which a small quantum dot is coupled symmetrically to several large quantum dots characterized by a charging energy E_c. Even if E_c is much smaller than the Kondo temperature T_K, the long-ranged…
We study triangular clusters of three spin-1/2 Kondo or Anderson impurities that are coupled to two conduction leads. In the case of Kondo impurities, the model takes the form of an antiferromagnetic Heisenberg ring with Kondo-like exchange…
The single impurity problem in a spinful Tomonaga-Luttinger liquid is studied numerically using path-integral Monte Carlo methods. The advantage of our approach is that the system allows for extensive analyses of charge and spin conductance…
The insertion of a magnetic $\pi$ flux into a quantum spin Hall insulator creates four localized, spin-charge separated states: the charge and spin fluxons with either charge $Q=\pm1$ or spin $S_z=\pm1/2$, respectively. In the presence of…
We study finite-frequency transport properties of the double-dot system recently constructed to observe the two-channel Kondo effect [R. M. Potok et al., Nature 446, 167 (2007)]. We derive an analytical expression for the…
Simple scaling consideration and NRG solution of the one- and two-channel Kondo model in the presence of a logarithmic Van Hove singularity at the Fermi level is given. The temperature dependences of local and impurity magnetic…
Magnetic impurities affect the transport properties of the helical edge states of quantum spin Hall insulators by causing single-electron backscattering. We study such a system in the presence of a Rashba spin-orbit interaction induced by…
We study a quantum impurity coupled to the edge states of a two-dimensional helical topological superconductor, i.e., to a pair of counterpropagating Majorana fermion edge channels with opposite spin polarizations. For an impurity described…
We adapt strong-coupling methods first used in the one-channel Kondo model to develop a simple description of the spin-$1\over 2$ two-channel Kondo model with channel anisotropy. Our method exploits spin-charge decoupling to develop a…