Related papers: Poor electronic screening in lightly doped Mott in…
We argue, based on band structure calculations and Eliashberg theory, that the observed decrease of $T_c$ of Al and C doped MgB$_2$ samples can be understood mainly in terms of a band filling effect due to the electron doping by Al and C. A…
YTiO3, as a prototypical Mott insulator, has been the subject of numerous experimental investigations of its electronic structure. The onset of absorption in optical conductivity measurements has generally been interpreted to be due to…
In topological insulators (TI), strong spin-orbit coupling results in non-trivial scattering processes of the surface states, whose effects include suppressed back scattering1, 2, 3, 4 weak anti-localization5, 6 and the possibility of an…
We present a detailed experimental study on the electrostatic interaction between a quantum dot and the metallic tip of a scanning force microscope. Our method allowed us to quantitatively map the tip-induced potential and to determine the…
This article reviews the effort to understand the physics of high temperature superconductors from the point of view of doping a Mott insulator. The basic electronic structure of the cuprates is reviewed, emphasizing the physics of strong…
A common method of adjusting the metal-insulator transition temperature of M$_{1}$ VO$_{2}$ is via disruption of the Peierls pairing by doping, or inputting stress or strain. However, since adding even small amounts of dopants will change…
Achieving fundamental understanding of insulator-to-metal transitions (IMTs) in strongly correlated systems and their persistent and reversible control via nonequilibrium drive are prime targets of current condensed matter research.…
The spatial variation of electronic states was imaged in the lightly doped Mott insulator Ca_{2-x}Na_{x}CuO_{2}Cl_{2} using scanning tunneling microscopy / spectroscopy (STM/STS). We observed nano-scale domains with a high local density of…
SmB$_6$, known to be a Kondo insulator, has received intense scrutiny in recent years due to its paradoxical experimental signatures: while some quantities show an insulating behavior, others point to a metallic state. This has led to the…
High-temperature superconductivity in cuprates emerges upon doping the parent Mott insulator. Robust signatures of the low-doped electronic state include a Hall carrier density that initially tracks the number of doped holes and the…
Mott state in 1T-TaS2 is predicted to host quantum spin liquids (QSL). However, its insulating mechanism is controversial due to complications from interlayer coupling. Here, we study the Mott state in monolayer 1T-NbSe2, an electronic…
We investigate the properties of the metallic state obtained by photo-doping carriers into a Mott insulator. In a strongly interacting system, these carriers have a long life-time, so that they can dissipate their kinetic energy to a phonon…
Topological insulators are bulk semiconductors that manifest in-gap massless Dirac surface states due to the topological bulk-boundary correspondence principle [1-3]. These surface states have been a subject of tremendous ongoing interest,…
In CaFe2As2, superconductivity can be achieved by applying a modest c-axis pressure of several kbar. Here we use scanning tunneling microscopy/spectroscopy (STM/S) to explore the STM tip pressure effect on single crystals of CaFe2As2. When…
We investigate the highly incoherent regime of hole-doped 2d Mott-Hubbard insulators at moderately small doping and temperatures T>=0.1J, where J is the exchange coupling. Within an extended dynamical mean-field theory of the t-J model and…
The motion of doped electrons or holes in an antiferromagnetic lattice with strong on-site Coulomb interactions touches one of the most fundamental open problems in contemporary condensed matter physics. The doped charge may strongly couple…
We investigate the nature and origin of the metal-insulator transition in Sr2Ru1-xTixO4 as a function of increasing Ti content (x). Employing detailed core, valence, and conduction band studies with x-ray and ultraviolet photoelectron…
The internal structure of doped holes in the Mott insulator may provide important insight into the physics of doped cuprates. Its observability via a single-particle probe by scanning tunneling spectroscopy (STS) and angle-resolved…
Stimulated emission of sensitized Erbium atoms is reported in silicon-rich silicon nitride waveguides. Visible pump and infrared probe measurements are carried out in waveguides fabricated from erbium-doped silicon rich silicon nitride. A…
We report scanning tunneling spectroscopy (STS) measurements of the gap properties of both ceramic MgB2 and c-axis oriented epitaxial MgB2 thin films. Both show a temperature dependent zero bias conductance peak and evidence for two…