Related papers: Zero bias anomaly in a two dimensional granular in…
We investigate transport in a granular metallic system at large tunneling conductance between the grains. We show that at low temperatures, $T\leq g_T\delta $, where $\delta$ is the single mean energy level spacing in a grain, the coherent…
A new technique permits high fidelity measurement of the tunneling density of states (TDOS) of the two-dimensional electron gas. The obtained TDOS contains no distortions arising from low 2D in-plane conductivity and includes the…
We report the first low temperature magnetotransport measurements on electrochemically fabricated atomic scale gold nanojunctions. As $T \to 0$, the junctions exhibit nonperturbatively large zero bias anomalies (ZBAs) in their differential…
We report on the observation of non-metallic electrical conduction, resistive switching, and a negative temperature coefficient of resistance in cluster-assembled nanostructured gold films above the electrical percolation and in…
It is shown that practically any physically relevant random distribution of offset charges destroys the Kosterlitz-Thouless-Berezinskii charge-unbinding phase transition in two dimensional normal and superconducting granular arrays and…
Tunnelling density of states (DoS) in Luttinger liquid has a dip at zero energy, commonly known as the zero-bias anomaly (ZBA). In the presence of a magnetic field, in addition to the zero-bias anomaly, the DoS develops two peaks separated…
High-impedance contacts made on the surface of Sr$_{0.88}$La$_{0.12}$CuO$_2$ superconducting thin films systematically display a zero-bias anomaly. We consider two-level systems (TLS) as the origin of this anomaly. We observe that the…
In an ultrathin topological insulator (TI) film, a hybridization gap opens in the TI surface states, and the system is expected to become either a trivial insulator or a quantum spin Hall insulator when the chemical potential is within the…
We studied the low-energy states of spin-1/2 quantum dots defined in InAs/InP nanowires and coupled to aluminium superconducting leads. By varying the superconducting gap, \Delta, with a magnetic field, B, we investigated the transition…
We study the effect of random offset charges in the insulator to conductor transition in systems of capacitively coupled grains, as realized in two-dimensional arrays of ultrasmall Josephson junctions. In presence of disorder, the…
We study the density of states (DoS) $\nu(E)$ in a normal-metallic (N) film contacted by a bulk superconductor (S). We assume that the system is diffusive and the SN interface is transparent. In the limit of thin N layer (compared to the…
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…
Adsorption of 1/3 monolayer of Sn on a heavily-doped p-type Si(111) substrate results in the formation of a hole-doped Mott insulator, with electronic properties that are remarkably similar to those of the high-Tc copper oxide compounds. In…
Tunneling spectroscopy of superconductors provides valuable insights into gap symmetry, quasiparticle dynamics, and pairing mechanisms. This paper explores spatial patterns of quasiparticle interference in the tunneling density of states…
We present zero-temperature simulations for the single-particle density of states of the Coulomb glass. Our results in three dimensions are consistent with the Efros and Shklovskii prediction for the density of states. Finite-temperature…
Electron tunneling experiments are used to probe Coulomb correlation effects in the single-particle density-of-states (DOS) of boron-doped silicon crystals near the critical density of the metal-insulator transition (MIT). At low energies,…
We are honored to dedicate this article to Emmanuel Rashba on the occasion of his 95 birthday. In the ideal disorder-free situation, a two-dimensional band gap insulator has an activation energy for conductivity equal to half the band gap,…
Disorder has different profound effects on superconducting thin films. For a large variety of materials, increasing disorder reduces electronic screening which enhances electron-electron repulsion. These fermionic effects lead to a…
Superfluid condensation can fundamentally be different from that predicted by the Bardeen-Cooper-Schrieffer (BCS) theory. In a broad class of low-carrier-density superconductors, such as granular aluminum, doped nitrides, and high-Tc…
Bilayer quantum Hall system at total filling factor $\nu=1$ shows a rich variety of broken symmetry ground states because of the competition between the interlayer and intralayer Coulomb interactions. When the layers are sufficiently close,…