Related papers: Zero bias anomaly in a two dimensional granular in…
The Efros-Shklovskii law for the conductivity of granular metals is interpreted as a result of a variable range cotunneling process. The cotunneling between distant resonant grains is predominantly elastic at low T << T_c, while it is…
We consider the effect of Coulomb interactions on the average density of states (DOS) of disordered low-dimensional metals for temperatures T and frequencies omega smaller than the inverse elastic life-time. Using the fact that long-range…
We present a tunneling study on single crystalline parent cuprate thin films, i.e. a series of Pr2CuO4+/-{\delta}(PCO) with tunable superconducting transition temperature. The zero-bias anomaly of differential conductance, well reported in…
Amorphous solids, and many disordered lattices, exhibit a remarkable qualitative and quantitative universality in their acoustic properties at temperature $\lesssim 3$K. This phenomenon is attributed to the existence of tunneling two level…
We compute the tunneling density of states of doped multi-wall nanotubes including disorder and electron-electron interactions. A non-conventional Coulomb blockade reflecting nonperturbative Altshuler-Aronov-Lee power-law zero-bias…
The tunneling into the {\em bulk} of a 2D electron system (2DES) in strong magnetic field is studied near the integer quantum Hall transitions. We present a nonperturbative calculation of the tunneling density of states (TDOS) for both…
Superconductor insulator transition in transverse magnetic field is studied in the highly disordered MoC film with the product of the Fermi momentum and the mean free path $k_F*l$ close to unity. Surprisingly, the Zeeman paramagnetic…
Granular conductors form an artificially engineered class of solid state materials wherein the microstructure can be tuned to mimic a wide range of otherwise inaccessible physical systems. At the same time, topological insulators (TIs) have…
We study the tunneling density of states (DoS) in the superconducting systems driven by Zeeman splitting E_Z into the paramagnetic phase. We show that, even though the BCS gap disappears, superconducting fluctuations cause a strong DoS…
The small energy anomaly in the single particle density of states of disordered interacting systems is studied for the zero dimensional case. This anomaly interpolates between the non--perturbative Coulomb blockade and the perturbative…
The origin of the intermediate anomalous metallic state in two-dimensional superconductor materials remains enigmatic. In the present paper, we observe such a state in a series of $\sim$9.0 nm thick Ta$_x$(SiO$_2$)$_{1-x}$ ($x$ being the…
We have made an experimental study of the tunneling density of states (DOS) in strong ferromagnetic thin films (CoFe) in proximity with a thick superconducting film (Nb) as a function of $d_F$, the ferromagnetic thickness. Remarkably, we…
Transport properties of granular systems are governed by Coulomb blockade effects caused by the discreteness of the electron charge. We show that, in the limit of vanishing mean level spacing on the grains, the low-temperature behavior of…
We investigate transport in a granular metallic system at large tunneling conductance between the grains, $g_T\gg 1$. We show that at low temperatures, $T\leq g_T\delta $, where $\delta$ is the single mean energy level spacing in a grain,…
Electronic transport in multiwall carbon nanotubes and semiconductor nanowires was compared. In both cases, the non ohmic behavior of the conductance, the so-called zero bias anomaly, shows a temperature dependence that scales with the…
Making use of generalized Eliashberg equations, we describe the Altshuler-Aronov (AA) effect and superconductivity on equal footing. We derive explicit expressions for the Coulomb pseudopotential in 3D, taking into account also the…
We present transport measurements on quench condensed granular Pb films in which the grains are 40-80\AA in diameter. These films show a cross over from an insulator to a superconductor behavior as the nominal thickness of the layer is…
We study the tunneling density of states (DoS) in the superconducting systems driven by Zeeman splitting $E_Z$ into the paramagnetic phase. We show that, even though the BCS gap disappears, superconducting fluctuations cause a strong DoS…
We perform combined resistivity and compressibility studies of two-dimensional hole and electron systems which show the apparent metal-insulator transition - a crossover in the sign of dR/dT with changing density. No thermodynamic anomalies…
We study the tunneling density of states (TDOS) of a disordered electronic system with Coulomb interaction on the insulating side of the Anderson localization transition. The average TDOS shows a critical behavior at high energies, with a…