Single-electron transistor with ferromagnetic outer electrodes and a nonmagnetic island is studied theoretically. Nonequilibrium electron-spin distribution in the island is caused by tunneling current. The dependences of the magnetoresistance ratio d on the bias and gate voltages show the dips which are directly related to the induced separation of Fermi levels for electrons with different spin...

Undoped hydrogenated microcrystalline silicon (lc-Si:H) layers were grown by the very high frequency glow discharge (VHF-GD) technique under various deposition conditions. The electronic transport properties under illumination were investigated by means of steady-state photoconductivity and steady-state photocarrier grating methods. Similarly to hydrogenated amorphous silicon (a-Si:H), power la...

This article provides a brief review of how various spectroscopies have been used to investitage many-body quantum phenomena in the context of ultracold Fermi gases. In particular, work done with RF spectroscopy, Bragg spectroscopy and lattice modulation spectroscopy is considered. The theoretical basis of these spectroscopies, namely linear response theory in the many-body quantum physics cont...

We report the discovery of gamma-ray emission from the Galactic globular cluster Terzan 5 using data taken with the Fermi Gamma-ray Space Telescope, from 2008 August 8 to 2010 January 1. Terzan 5 is clearly detected in the 0.5–20 GeV band by Fermi at ∼ 27σ level. This makes Terzan 5 as the second gamma-ray emitting globular cluster seen by Fermi after 47 Tuc. The energy spectrum of Terzan 5 is ...

We describe a characteristic signature of dark matter (DM) annihilation or decay into gamma-rays. We show that if the total angular momentum of the initial DM particle(s) vanishes, and helicity suppression operates to prevent annihilation/decay into light fermion pairs, then the amplitude for the dominant 3-body final state ffγ has a unique form dictated by gauge invariance. This amplitude and ...

We investigate excitations in one-dimensional granular crystals, i.e. chains of solid beads with nonlinear interaction forces. These chains have attracted attention because of their relative experimental simplicity and interesting dynamics. They can be modelled as chains of coupled oscillators in a model reminiscent of the celebrated Fermi-Pasta-Ulam (FPU) equations. The nonlinearity of the int...

We discuss finite density configurations on probe D-branes, in the presence of worldvolume fermions. To this end we consider a phenomenological model whose bosonic sector is governed by the DBI action, and whose charged sector is purely fermionic. In this model, we demonstrate the existence of a compact worldvolume embedding, stabilized by a Fermi surface on the D-brane. The finite density stat...

We derive the equilibrium and transport properties of metals using renormalization group equations and finite-size scaling. Particular attention is given to the well-known cases of Fermi and Luttinger liquids. An important subtlety is that the temperature dependence of many transport coefficients is determined by “dangerous” irrelevant operators. We also characterize violations of Fermi or Lutt...

A Thomas-Fermi model of a spherical shell of positive charge is investigated, under various boundary conditions. The electron distribution and the ionization charge are given particular attention.

By employing the theoretical method based on tight-binding, we study electronic band structure of single-wall carbon nanotube (CNT) superlattices, which the system is the made of the junction between the zigzag and armchair carbon nanotubes. Exactly at the place of connection, it is appeared the pentagon–heptagon pairs as topological defect in carbon hexagonal network. The calculations are base...