13,778 research outputs found
Magnetic-field induced resistivity minimum with in-plane linear magnetoresistance of the Fermi liquid in SrTiO3-x single crystals
We report novel magnetotransport properties of the low temperature Fermi
liquid in SrTiO3-x single crystals. The classical limit dominates the
magnetotransport properties for a magnetic field perpendicular to the sample
surface and consequently a magnetic-field induced resistivity minimum emerges.
While for the field applied in plane and normal to the current, the linear
magnetoresistance (MR) starting from small fields (< 0.5 T) appears. The large
anisotropy in the transverse MRs reveals the strong surface interlayer
scattering due to the large gradient of oxygen vacancy concentration from the
surface to the interior of SrTiO3-x single crystals. Moreover, the linear MR in
our case was likely due to the inhomogeneity of oxygen vacancies and oxygen
vacancy clusters, which could provide experimental evidences for the unusual
quantum linear MR proposed by Abrikosov [A. A. Abrikosov, Phys. Rev. B 58, 2788
(1998)].Comment: 5 pages, 4 figure
Landauer transport model for Hawking radiation from a Reissner-Nordstrom black hole
The recent work of Nation et al in which Hawking radiation energy and entropy
flow from a black hole can be regarded as a one-dimensional (1D) Landauer
transport process is extended to the case of a Reissner-Nordstrom (RN) black
hole. It is found that the flow of charge current can also be transported via a
1D quantum channel except the current of Hawking radiation. The maximum entropy
current, which is shown to be particle statistics independence, is also
obtained
Metallic state in La-doped YBaCuO thin films with -type charge carriers
We report hole and electron doping in La-doped YBaCuO(YBCO) thin
films synthesized by pulsed laser deposition technique and subsequent
\emph{in-situ} postannealing in oxygen ambient and vaccum. The -type samples
show a metallic behavior below the Mott limit and a high carrier density of
10 cm at room temperature (\emph{T}) at the
optimally reduced condition. The in-plane resistivity () of the
-type samples exhibits a quadratic \emph{T} dependence in the
moderate-\emph{T} range and shows an anomaly at a relatively higher \emph{T}
probably related to pseudogap formation analogous to underdoped
NdCeCuO (NCCO). Furthermore, (T), \emph{T} and
\emph{T} with minimum resistivity (\emph{T}) were investigated in both
- and -side. The present results reveal the - asymmetry (symmetry)
within the metallic-state region in an underdoped cuprate and suggest the
potential toward ambipolar superconductivity in a single YBCO system.Comment: 4 pages, 5 figure
Mass movement susceptibility mapping using satellite optical imagery compared with InSAR monitoring: Zigui County, Three Gorges region, China
Mass movements on steep slopes are a major hazard to
communities and infrastructure in the Three Gorges
region, China. Developing susceptibility maps of mass
movements is therefore very important in both current
and future land use planning. This study employed
satellite optical imagery and an ASTER GDEM (15 m)
to derive various parameters (namely geology; slope
gradient; proximity to drainage networks and proximity
to lineaments) in order to create a GIS-based map of
mass movement susceptibility. This map was then
evaluated using highly accurate deformation signals
processed using the Persistent Scatterer (PS) InSAR
technique. Areas of high susceptibility correspond well
to points of high subsidence, which provides a strong
support of our susceptibility map
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