相关论文: $\mathbb{Z}_3$ parafermion in the double charge-Ko…
We clarify the two-channel Kondo effect in the seven-orbital Anderson model hybridized with $\Gamma_8$ conduction electrons by employing a numerical renormalization group method.From the numerical analysis for the case with two local $f$…
We present results of extensive finite-temperature Quantum Monte Carlo simulations on a SU(2) symmetric S=1/2 quantum antiferromagnet with a four-spin interaction [Sandvik, Phys. Rev. Lett. 98, 227202 (2007)]. Our simulations, which are…
Quantum dot devices allow one to access the critical point of the two-channel Kondo model. The effective critical theory involves a free Majorana fermion quasiparticle localized on the dot. As a consequence, this critical point shows both…
Quantum criticality beyond the Landau paradigm represents a fundamental problem in condensed matter and statistical physics. Heavy fermion systems with multipolar degrees of freedom can play an important role in the search for its universal…
We investigate a four-impurity Anderson model where localized orbitals are located at vertices of a regular tetrahedron and find a novel fixed point in addition to the ordinary Fermi liquid phase. That is characterized by unscreened scalar…
The Kondo breakdown scenario has been claimed to allow the $T$-linear resistivity in the vicinity of the Kondo breakdown quantum critical point, two cornerstones of which are the dynamical exponent $z = 3$ quantum criticality for…
We demonstrate that spin-charge separation can occur in two dimensions and note its confluence with superconductivity, topology, gauge theory, and fault-tolerant quantum computation. We construct a microscopic Ising-like model and, at a…
Motivated by recent experiments, we study a quasi-one dimensional model of a Kondo lattice with Ferromagnetic coupling between the spins. Using bosonization and dynamical large-N techniques we establish the presence of a Fermi liquid and a…
Parafermion zero modes are exotic emergent excitations that can be considered as $\mathbb{Z}_n$ generalizations of Majorana fermions. Present in fractional quantum Hall-superconductor hybrid systems, among others, they can serve as…
A spin-fermion model that captures the charge-transfer properties of Cu-based high critical temperature superconductors is introduced and studied via Monte Carlo simulations. The strong Coulomb repulsion among $d$-electrons in the Cu…
A modified version of the spinless Anderson model is studied by means of the continuous-time quantum Monte Carlo method. This study is motivated by the peculiar heavy-fermion behavior observed in certain Samarium compounds, which is…
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 study the transmission through a double quantum-dot system in the Kondo regime. An exact expression for the transmission coefficient in terms of fully interacting many-body Green's functions is obtained. By mapping the system into an…
We study charge transport through a floating mesoscopic superconductor coupled to counterpropagating fractional quantum Hall edges at filling fraction $\nu=2/3$. We consider a superconducting island with finite charging energy and…
We present a systematic investigation of all sixteen marginally relevant fermion-fermion interactions in two-dimensional time-reversal symmetry-breaking kagom\'{e} semimetals hosting a quadratic band crossing point. Employing a…
A Kondo model for three spin-one-half impurities placed at the vertices of an equilateral triangle is studied using the numerical renormalization-group method. The impurity spins can form two frustrated doublets which, because of the…
The competition between intertube hopping processes and density-density interactions is investigated in one-dimensional quantum dipolar bosons systems of N coupled tubes at zero temperature. Using a phenomenological bosonization approach,…
We study a simple model of three-dimensional fermions close to a quadratic band touching point, built from the celebrated Luttinger single-particle Hamiltonian and an attractive contact interaction between the particles. Such a system…
The Kondo effect in condensed-matter systems manifests itself most sharply in their transport measurements. Here we propose an analogous transport signature of the orbital Kondo effect realized with ultracold atoms. Our system consists of…
The notion of fractional charges was up until now reserved for quasiparticle excitations emerging in strongly correlated quantum systems, such as Laughlin states in the fractional quantum Hall effect, Luttinger quasiparticles, or…