1,567 research outputs found
Spin-dependent resonant tunneling through semimetallic ErAs quantum wells
Resonant tunneling through semimetallic ErAs quantum wells embedded in GaAs
structures with AlAs barriers was recently found to exhibit an intriguing
behavior in magnetic fields which is explained in terms of tunneling selection
rules and the spin-polarized band structure including spin-orbit coupling.Comment: 4 pages, figures supplied as self-unpacking figures.uu, uses
epsfig.sty to incorporate figures in preprin
Doping effect on the evolution of the pairing symmetry in n-type superconductor near antiferromagnetic phase boundary
We present the investigation results of the in-plane \{rho}(T) resistivity
tensor at the temperature range 0.4-40 K in magnetic fields up to 90kOe (H||c,
J||ab) for electron-doped Nd{2-x}Ce{x}CuO{4+{\delta}} with different degree of
disorder near antiferromagnetic - superconducting phase boundary. We have
experimentally found that for optimally doped compound both the upper critical
field slope and the critical temperature decrease with increasing of the
disorder parameter (d-wave pairing) while in the case of the underdoped system
the critical temperature remains constant and (dHc2/dT)|Tc increases with
increasing of the disorder (s-wave pairing). These features suggest a possible
implementation of the complex mixture state as the (s+id)-pairing.Comment: 9 pages, 2 figure
The Construction and Parameters of Forward Hadron Calorimeter (FHCAL) at MPD/NICA
Forward hadron calorimeter (FHCAL) at MPD/NICA experimental setup is intended for the measurements of the geometry of heavy ions collisions, namely, the collision centrality and the orientation of the reaction plane. FHCAL consists of two identical arms placed at the left/right sides from the beam collision point. This is a modular lead- scintillator compensating calorimeter designed to measure the energy distribution of the projectile nuclei fragments (spectators) and forward going particles close to the beam rapidity
Diffraction based Hanbury Brown and Twiss interferometry performed at a hard x-ray free-electron laser
We demonstrate experimentally Hanbury Brown and Twiss (HBT) interferometry at
a hard X-ray Free Electron Laser (XFEL) on a sample diffraction patterns. This
is different from the traditional approach when HBT interferometry requires
direct beam measurements in absence of the sample. HBT analysis was carried out
on the Bragg peaks from the colloidal crystals measured at Linac Coherent Light
Source (LCLS). We observed high degree (80%) spatial coherence of the full beam
and the pulse duration of the monochromatized beam on the order of 11 fs that
is significantly shorter than expected from the electron bunch measurements.Comment: 32 pages, 10 figures, 2 table
Revealing three-dimensional structure of individual colloidal crystal grain by coherent x-ray diffractive imaging
We present results of a coherent x-ray diffractive imaging experiment
performed on a single colloidal crystal grain. The full three-dimensional (3D)
reciprocal space map measured by an azimuthal rotational scan contained several
orders of Bragg reflections together with the coherent interference signal
between them. Applying the iterative phase retrieval approach, the 3D structure
of the crystal grain was reconstructed and positions of individual colloidal
particles were resolved. As a result, an exact stacking sequence of hexagonal
close-packed layers including planar and linear defects were identified.Comment: 8 pages, 5 figure
Tests of the Electromagnetic Calorimeter for HADES Experiment at GSI
Measurements of mass spectra of dilepton pairs in the HADES experiment in the energy domain of SIS18 and SIS100 (FAIR, Darmstadt, Germany) are very important for studing the excitation function of the virtual photon radiation from dense nuclear matter. A detail study of this phenomenon in the intermediate mass region (0.14 < M < 0.6 GeV/c2) demands precise measurements of inclusive cross sections o
Electron Spin Polarization in Resonant Interband Tunneling Devices
We study spin-dependent interband resonant tunneling in double-barrier
InAs/AlSb/ GaMnSb heterostructures. We demonstrate that these structures can be
used as spin filters utilizing spin-selective tunneling of electrons through
the light-hole resonant channel. High densities of the spin polarized electrons
injected into bulk InAs make spin resonant tunneling devices a viable
alternative for injecting spins into a semiconductor. Another striking feature
of the proposed devices is the possibility of inducing additional resonant
channels corresponding to the heavy holes. This can be implemented by
saturating the in-plane magnetization in the quantum well.Comment: 11 pages, 4 eps figure
- …