Related papers: Mott transition in granular aluminum
Quantum transitions between the Mott insulator and metals by controlling filling in two-dimensional square lattice are characterized by a large dynamical exponent $z=4$ where the origin of unusual metallic properties near the Mott insulator…
We study two-component fermions in optical lattices with spatially alternating on-site interactions using dynamical mean-field theory. Calculating the quasi-particle weight, double occupancy, and order parameters for each sublattice, we…
We report measurements of the energy gap of granular aluminum films by THz spectroscopy. We find that as the grains progressively decouple, the coupling ratio $2\Delta(0)/k_{B}T_{c}$ increases above the BCS weak coupling ratio $3.53$, and…
When electron-electron interaction dominates over other electronic energy scales, exotic, collective phenomena often emerge out of seemingly ordinary matter. The strongly correlated phenomena, such as quantum spin liquid and unconventional…
The first order magneto-structural transition ($T_t\simeq95$ K) and magnetocaloric effect in MnNiGe$_{0.9}$Ga$_{0.1}$ are studied via powder x-ray diffraction and magnetization measurements. Temperature dependent x-ray diffraction…
We report on resistivity measurements in La$_{0.67}$Ca$_{0.33}$MnO$_{3}$ and Nd$_{0.7}$Sr$_{0.3}$MnO$_{3}$ thin films in order to elucidate the underlying mechanism for the CMR behavior. The experimental results are analyzed in terms of…
High-quality epitaxial SrVO3 (SVO) thin films of various thicknesses were grown on (001)-oriented LSAT substrates by pulsed electron-beam deposition technique. Thick SVO films (~25 nm) exhibited metallic behavior with the electrical…
Spin Hall magnetoresistance (SMR) refers to a resistance change in a metallic film reflecting the magnetization direction of a magnet attached to the film. The mechanism of this phenomenon is spin exchange between conduction-electron spins…
The pressure driven Mott-transition in Chromium doped V2O3 films is investigated by direct electrical measurements on polycrystalline films with thicknesses down to 10 nm, and doping concentrations of 2%, 5% and 15%. A change in resistivity…
The fundamental building blocks of modern silicon-based microelectronics, such as double gate transistors in non-volatile Flash memories, are based on the control of electrical resistance by electrostatic charging. Flash memories could soon…
Metallic transition-metal oxides undergo a metal-to-insulator transition (MIT) as the film thickness decreases across a ritical thickness of several monolayers (MLs), but its driving mechanism remains controversial. We have studied the…
Transport and magnetic studies of Ca3Ru2O7 for temperatures ranging from 0.4 K to 56 K and magnetic fields, B, up to 45 T leads to strikingly different behavior when the field is applied along the different crystal axes. A ferromagnetic…
The spin-orbit Mott insulator Sr3Ir2O7 provides a fascinating playground to explore insulator-metal transition driven by intertwined charge, spin, and lattice degrees of freedom. Here, we report high pressure electric resistance and…
The gas-liquid transition is a first-order transition terminating at a finite-temperature critical point with diverging density fluctuations. Mott transition, a metal-insulator transition driven by Coulomb repulsion between electrons, has…
Effects of the electron-electron interaction in the two-dimensional flux phase are investigated. We treat the half-filled Hubbard model with a magnetic flux $\pi$ per plaquette by the quantum Monte Carlo method. When the interaction is…
In this review, we outline the important results on the resistivity encountered by an electron in magnetically ordered materials. The mechanism of the collision between the electron and the lattice spins is shown. Experiments on the spin…
We report on the first experimental observation of an apparent metal insulator transition in a 2D electron gas confined in an InAs quantum well. At high densities we find that the carrier mobility is limited by background charged impurities…
In strongly correlated electronic systems, such as manganites, the global transport behavior depends sensitively on the spin ordering, whose alteration often requires a large external magnetic field. Here we show that the spin ordering in…
We report on a new electromagnetic phenomenon that emerges in Mott insulators, i.e., materials that do not conduct electricity because of strong electronic Coulomb repulsion. The phenomenon manifests as antiferromagnetic ordering due to…
Frequency shifts and nuclear relaxations of 13C NMR of the metal-insulator alternating material, (Me-3,5-DIP)[Ni(dmit)2]2, are presented. The NMR absorption lines originating from metallic and insulating layers are well resolved, which…