Related papers: Spin-charge separation and simultaneous spin and c…
The low energy region of certain transition metal compounds reveals dramatic correlation effects between electrons, which can be studied by photoelectron spectroscopy. Theoretical investigations are often based on multi-orbital impurity…
We study the Kondo effect due to the nonmagnetic impurity, e.g., Zn, in high-T_c cuprates based on the spin-change separated state. In the optimal or overdoped case with the Kondo screening, the residual resistivity is dominated by the…
We present a one dimensional model of electrons coupled to localized moments of spin $S\ge 1$ in which magnetism and superconductivity interplay in a nontrivial manner. This model has a non-Fermi liquid ground state of the chiral spin…
We present a comprehensive analysis of the magnetic excitations and electronic properties of fully quantum double-exchange ferromagnets, i.e., systems where ferromagnetic ordering emerges from the competition between spin, charge, and…
For a mobile spin-1/2 impurity, coupled antiferromagnetically to a one-dimensional gas of fermions, perturbative ideas have been used to argue in favor of two-channel Kondo behavior of the impurity spin. Here we combine general…
Spin-flip scattering from magnetic impurities has a strong pair-breaking effect in $s$-wave superconductors where increasing the concentration of impurities rapidly destroys superconductivity. For small Kondo temperature $T_K$ the…
A spin-1/2 magnetic impurity coupled to a one-dimensional correlated electron system have been studied by applying the density renormalization group method. The Kondo temperature is substantially enhanced by strong repulsive interactions in…
Magnetic impurities are responsible for many interesting phenomena in condensed matter systems, notably the Kondo effect and quantum phase transitions. Here we present a holographic model of a magnetic impurity that captures the main…
We study the interplay of superconducting and ferromagnetic correlations on charge transport in different geometries with a focus on both a quantum point contact as well as a quantum dot in the even and the odd state with and without…
A new type of Kondo effect peculiar to unconventional superconductors is studied theoretically by using the Wilson's numerical renormalization group method. In this case, an angular momentum of a Cooper pair plays an important role in the…
Particle-hole symmetry breaking perturbation in two-channel pseudospin Kondo problem is studied by the numerical renormalization-group method. It is shown that the repulsion between conduction electrons at the impurity site and the single…
Dynamical tunneling systems have been proposed earlier to display a two-channel Kondo effect, the orbital index of the particle playing the role of a pseudospin in the equivalent Kondo problem, and the spin being a silent channel index.…
We demonstrate that a boundary defect in the single spin-$\frac{1}{2}$ quantum $XX$ chain exhibits two-channel Kondo physics. Due to the presence of the defect, the edge spin fractionalizes into two Majorana fermions, out of which one…
We use co-tunneling spectroscopy to investigate spin-, orbital-, and spin-orbital Kondo transport in a strongly confined system of InAs double quantum dots (QDs) parallel-coupled to source and drain. In the one-electron transport regime,…
Using the time-evolving block decimation, we study the spin transport through spin-1/2 and spin-1 XXZ chains subjected to an external magnetic field and contacted to noninteracting fermionic leads. For generic system-lead couplings, the…
We study the microscopic mechanism controlling the interplay between local charge and local spin fluctuations in correlated electron systems via a thorough investigation of the generalized on-site charge susceptibility of several…
We develop a general Bethe Ansatz formalism for diagonalizing an integrable model of a magnetic impurity of arbitrary spin coupled ferro- or antiferromagnetically to a chain of interacting electrons. The method is applied to an open chain,…
The scaling properties of the conductance of a Kondo impurity connected to two leads that are in or out of equilibrium has been extensively studied, both experimentally and theoretically. From these studies, a consensus has emerged…
We study the competition between Kondo physics and dissipation within an Anderson model of a magnetic impurity level that hybridizes with a metallic host and is also coupled, via the impurity charge, to the displacement of a bosonic bath…
Molecular electronic devices currently serve as a platform for studying a variety of physical phenomena only accessible at the nanometer scale. One such phenomenon is the highly correlated electronic state responsible for the Kondo effect,…