4,140 research outputs found
Electrical transport across Au/Nb:SrTiO3 Schottky interface with different Nb doping
We have investigated electron transport in Nb doped SrTiO single crystals
for two doping densities. We find that the resistivity and mobility are
temperature dependent in both whereas the carrier concentration is almost
temperature invariant. We rationalize this using the hydrogenic theory for
shallow donors. Further, we probe electrical transport across Schottky
interfaces of Au on TiO terminated n-type SrTiO. Quantitative analysis
of macroscopic I-V measurements reveal thermionic emission dominated transport
for the low doped substrate whereas it deviates from such behavior for the high
doped substrate. This work is relevant for designing devices to study
electronic transport using oxide-semiconductors.Comment: 10 Pages, 3 Figure
Comparison of hot-electron transmission in ferromagnetic Ni on epitaxial and polycrystalline Schottky interfaces
The hot-electron attenuation length in Ni is measured as a function of energy
across two different Schottky interfaces viz. a polycrystalline Si(111)/Au and
an epitaxial Si(111)/NiSi_2 interface using ballistic electron emission
microscopy (BEEM). For similarly prepared Si(111) substrates and identical Ni
thickness, the BEEM transmission is found to be lower for the polycrystalline
interface than for the epitaxial interface. However, in both cases, the
hot-electron attenuation length in Ni is found to be the same. This is
elucidated by the temperature-independent inelastic scattering, transmission
probabilities across the Schottky interface, and scattering at dissimilar
interfaces.Comment: 5 pages, 5 figure
Geometric discord and Measurement-induced nonlocality for well known bound entangled states
We employ geometric discord and measurement induced nonlocality to quantify
non classical correlations of some well-known bipartite bound entangled states,
namely the two families of Horodecki's (, and
dimensional) bound entangled states and that of Bennett etal's in
dimension. In most of the cases our results are analytic and both
the measures attain relatively small value. The amount of quantumness in the
bound entangled state of Benatti etal and the state
having the same matrix representation (in computational basis) is same.
Coincidently, the Werner and isotropic states also exhibit the
same property, when seen as dimensional states.Comment: V2: Title changed, one more state added; 11 pages (single column), 2
figures, accepted in Quantum Information Processin
Study of Dissipative Collisions of Ne (7-11 MeV/nucleon) + Al
The inclusive energy distributions of complex fragments (3 Z 9)
emitted in the reactions Ne (145, 158, 200, 218 MeV) + Al have
been measured in the angular range 10 - 50. The fusion-fission and
the deep-inelastic components of the fragment yield have been extracted using
multiple Gaussian functions from the experimental fragment energy spectra. The
elemental yields of the fusion-fission component have been found to be fairly
well exlained in the framework of standard statistical model. It is found that
there is strong competition between the fusion-fission and the deep-inelastic
processes at these energies. The time scale of the deep-inelastic process was
estimated to be typically in the range of 10 - 10 sec.,
and it was found to decrease with increasing fragment mass. The angular
momentum dissipations in fully energy damped deep-inelastic process have been
estimated from the average energies of the deep-inelastic components of the
fragment energy spectra. It has been found that, the estimated angular momentum
dissipations, for lighter fragments in particular, are more than those
predicted by the empirical sticking limit.Comment: 16 pages, 9 figure
Sharp change over from compound nuclear fission to shape dependent quasi fission
Fission fragment mass distribution has been measured from the decay of
Bk nucleus populating via two entrance channels with slight difference
in mass asymmetries but belonging on either side of the Businaro Gallone mass
asymmetry parameter. Both the target nuclei were deformed. Near the Coulomb
barrier, at similar excitation energies the width of the fission fragment mass
distribution was found to be drastically different for the N +
Th reaction compared to the B + U reaction. The entrance
channel mass asymmetry was found to affect the fusion process sharply.Comment: 4 pages,6 figure
Evidence of large nuclear deformation of S formed in Ne + C reaction
Deformations of hot composite S formed in the reaction Ne
( 7 -- 10 MeV/nucleon) + C have been estimated from the respective
inclusive -particle evaporation spectra. The estimated deformations for
S have been found to be much larger than the `normal' deformations
of hot, rotating composites at similar excitations. This further confirms the
formation of highly deformed long-lived configuration of Ne + C
at high excitations ( 70 -- 100 MeV) -- which was recently indicated from
the analysis of the complex fragment emission data for the same system.
Exclusive -particle evaporation spectra from the decay of hot composite
S also show similar behaviour.Comment: 9 pages, 6 figure
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