Related papers: Is a doped 'Kondo' insulator different from doped …
We theoretically investigate the possibility of establishing ferromagnetism in the topological insulator Bi2Se3 via magnetic doping of 3d transition metal elements. The formation energies, charge states, band structures, and magnetic…
We report an observation of metal-insulator transition in a thin film of SnSe$_2$. The room-temperature carrier concentration of SnSe$_2$ film was increased by electrostatic doping to 1.14$\times$ 10$^{13}$ cm$^{-2}$. A crossover from…
The temperature dependence of a system exhibiting a `metal-insulator transition in two dimensions at zero magnetic field' (MIT) is studied up to 90K. Using a classical scattering model we are able to simulate the non-monotonic temperature…
We consider the form of the charge density nano-scale configurations in underdoped states of planar antiferromagnetic insulators in the framework of a soft variant of Faddeev-Niemi model. It is shown that there is such a level of doping and…
The influence of He+ ion irradiation on the transport and magnetic properties of epitaxial layers of a diluted magnetic semiconductor (DMS) (In,Fe)Sb, a two-phase (In,Fe)Sb composite and a nominally undoped InSb semiconductor has been…
We have carried out an investigation of the structural, magnetic, transport and superconducting properties of Fe$_{1+z}$Te$_{1-x-y}$Se$_x$S$_y$ ceramic compounds, for $z=0$ and some specific Se (0$\leq$ x $\leq$ 0.5) and S (0 $\leq$ y…
The conductivity of a granular metal or an array of quantum dots usually has the temperature dependence associated with variable range hopping within the soft Coulomb gap of density of states. This is difficult to explain because neutral…
The carrier type and density in Bi2Se3 single crystals are systematically tuned by introducing a calcium (Ca) dopant. A carrier density of ~1x1017 cm-3 which corresponds to ~25 meV in the Fermi energy is obtained in both n- and p-type…
We report results of low-temperature thermodynamic and transport measurements of Pb_{1-x}Tl_{x}Te single crystals for Tl concentrations up to the solubility limit of approximately x = 1.5%. For all doped samples, we observe a…
The Hall conductivity in the magnetic-field-induced spin-density-wave (FISDW) state of the quasi-one-dimensional organic conductors (TMTSF)$_2$X at a finite temperature is calculated. The temperature dependence of the Hall conductivity is…
We investigate the Kondo effect in two-dimensional disordered electron systems using a finite-temperature quantum Monte Carlo method. Depending on the position of a magnetic impurity, the local moment is screened or unscreened by the spin…
We report measurements of the temperature-dependent conductivity in a silicon metal-oxide-semiconductor field-effect transistor that contains sodium impurities in the oxide layer. We explain the variation of conductivity in terms of Coulomb…
A comparative study of the effect of Fe and Ni doping on the bismuth based perovskite La0.6Bi0.4MnO3.1, a projected spintronics magnetic semiconductor has been carried out. The doped systems show an expressive change in magnetic ordering…
A systematic LSDA+U study of doping effects on the electronic and structural properties of single layer CoO2 is presented. Undoped CoO2 is a charge transfer insulator within LSDA+U and a metal with a high density of states (DOS) at the…
We report a study of the La$_{1-x}$Ce$_x$FeSiH solid solution ($0 \leq x \leq 1$), a family of intermetallic hydrides of ZrCuSiAs-type structure, with space group $P4/nmm$. For low cerium concentrations $x \leq 0.20$, we observe the…
We report on a metal-insulator transition in the LaAlO3-SrTiO3 interface electron system, of which the carrier density is tuned by an electric gate field. Below a critical carrier density n_c ranging from 0.5-1.5 * 10^13/cm^2, LaAlO3-SrTiO3…
Combining ab initio calculations and effective models derived from them, we discuss the electronic structure of oxygen doped gold chains when one Au atom is replaced by any transition-metal atom of the $3d$ series. The effect of O doping is…
A central question in the high temperature cuprate superconductors is the fate of the parent Mott insulator upon charge doping. Here we use scanning tunneling microscopy to investigate the local electronic structure of lightly doped cuprate…
We study the 2D Kondo insulators in a uniform magnetic field using quantum Monte Carlo simulations of the particle-hole symmetric Kondo lattice model and a mean field analysis of the Periodic Anderson model. We find that the field induces a…
We present a unified, global perspective on the magnetic properties of strongly disordered electronic systems, with special emphasis on the case where the ground state is metallic. We review the arguments for the instability of the…