Related papers: Gap-anisotropic model for the narrow-gap Kondo ins…
In Kondo insulators the many-body Kondo lattice effect drives the formation of bands containing heavy charge carriers with a hybridization gap, leading to insulating properties. These renormalized bands can host non-trivial topologies…
Kondo insulators and in particular their non-cubic representatives have remained poorly understood. Here we report on the development of an anisotropic energy pseudogap in the tetragonal compound CeRu$_4$Sn$_6$ employing optical…
The recent discovery of topological Kondo insulating behaviour in strongly correlated electron systems has generated considerable interest in Kondo insulators both experimentally and theoretically. The Kondo semiconductors CeT2Al10 (T=Fe,…
The Kondo system CeRu$_4$Sn$_6$ shows a strong anisotropy in its electric, optic and magnetic properties. We employ density functional theory plus dynamical mean field theory and show that the predominant Ce-$f$ state has total angular…
Spin dynamics in the new Kondo insulator compound CeRu2Al10 has been studied using unpolarized and polarized neutron scattering on single crystals. In the unconventional ordered phase forming below T0 = 27.3 K, two excitation branches are…
Below a characteristic temperature, due to hybridisation effects Kondo insulators exhibit a gap in the electronic density of states and behave like semiconductors. By using Gd3+ electron spin resonance (ESR), the compound CeNiSn was…
We propose the notion of spin-selective Kondo insulator, which provides a fundamental mechanism to describe the ferromagnetic phase of the Kondo lattice model with antiferromagnetic coupling. This unveils a remarkable feature of the…
A new LDA+U band calculation is performed on the Kondo insulator material YbB$_{12}$ and an energy gap of about 0.001Ryd is obtained. Based on this, a simple tight-binding model with 5d$\epsilon$ and 4f $\Gamma_8$ orbitals on Yb atoms and…
Semimetallic CeNiSn is shown to transform into a Kondo semiconductor upon the substitution of few percent of Sb for Sn. The full-gap formation is not decisively influenced by the atomic disorder introduced by the substitution. Instead, the…
We present a new method to compute the electronic structure of correlated materials combining the hybrid functional method with the dynamical mean-field theory. As a test example of the method we study cerium sesquioxide, a strongly…
Kondo insulators (KIs) are strongly correlated materials in which the interactions between 4f and conduction electrons lead to a hybridization gap opening at low temperature 1-2. SmB6 is a typical KI, but its resistivity does not diverge at…
Magnetic field effects in Kondo insulators are studied theoretically, using a local moment approach to the periodic Anderson model within the framework of dynamical mean-field theory. Our main focus is on field-induced changes in…
It is demonstrated that a {\veck}-dependence of the hybridization matrix element between $f$- and conduction electrons can give rise to an anisotropic hybridization gap of heavy fermions if the filling of electrons corresponds to that of…
In low temperature scanning tunneling microscopy (STM) experiments a cerium adatom on Ag(100) possesses two discrete states with significantly different apparent heights. These atomic switches also exhibit a Kondo-like feature in…
We examine how the properties of the Kondo insulators change when the symmetry of the underlying crystal field multiplets is taken into account. We employ the Anderson lattice model and consider its low-energy physics. We show that in a…
Accurate calculations of strongly correlated materials remain a formidable challenge in condensed matter physics, particularly due to the computational demand of conventional methods. This paper presents an efficient solver for dynamical…
It follows from our analysis of CeRhSb that the formation of Kondo insulator state due to the presence of the collective spin singlet state is strongly reduced by its doping with various dopants when their amount exceeds 8--10\%, regardless…
We use scanning tunneling microscopy to investigate the (001) surface of cleaved SmB6 Kondo insulator. Variable temperature dI/dV spectroscopy up to 60 K reveals a gap-like density of state suppression around the Fermi level, which is due…
We investigate the ultrafast dynamics of the quasi-one-dimensional Kondo lattice CeCo$_2$Ga$_8$ using optical pump-probe spectroscopy. Time-resolved pump-probe reflectivity measurements reveal a strong anisotropy in the photoinduced…
We investigated the electronic structure of the enigmatic CeRh$_3$B$_2$ using resonant inelastic scattering and x-ray absorption spectroscopy in combination with $ab$ $initio$ density functional calculations. We find that the Rh 4$d$ states…