3,139 research outputs found
Anomalous thermoelectric effects of ZrTe in and beyond the quantum limit
Thermoelectric effects are more sensitive and promising probes to topological
properties of emergent materials, but much less addressed compared to other
physical properties. Zirconium pentatelluride (ZrTe) has inspired active
investigations recently because of its multiple topological nature. We study
the thermoelectric effects of ZrTe in a magnetic field and find several
anomalous behaviors. The Nernst response has a steplike profile near zero field
when the charge carriers are electrons only, suggesting the anomalous Nernst
effect arising from a nontrivial profile of Berry curvature. Both the
thermopower and Nernst signal exhibit exotic peaks in the strong-field quantum
limit. At higher magnetic fields, the Nernst signal has a sign reversal at a
critical field where the thermopower approaches to zero. We propose that these
anomalous behaviors can be attributed to the Landau index inversion, which is
resulted from the competition of the dependence of the Dirac-type
Landau bands and linear- dependence of the Zeeman energy ( is the
magnetic field). Our understanding to the anomalous thermoelectric properties
in ZrTe opens a new avenue for exploring Dirac physics in topological
materials.Comment: 6 pages, 4 figure
Providing appropriate social support to prevention of depression for high-anxious sufferers
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordNational Natural Science Foundation of ChinaFundamental Research Funds for the Central Universities, ChinaChina Postdoctoral Science FoundationFund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shaanxi Provinc
Incommensurate spin correlations in highly oxidized cobaltates LaSrCoO
We observe quasi-static incommensurate magnetic peaks in neutron scattering
experiments on layered cobalt oxides La2-xSrxCoO4 with high Co oxidation states
that have been reported to be paramagnetic. This enables us to measure the
magnetic excitations in this highly hole-doped incommensurate regime and
compare our results with those found in the low-doped incommensurate regime
that exhibit hourglass magnetic spectra. The hourglass shape of magnetic
excitations completely disappears given a high Sr doping. Moreover, broad
low-energy excitations are found, which are not centered at the incommensurate
magnetic peak positions but around the quarter-integer values that are
typically exhibited by excitations in the checkerboard charge ordered phase.
Our findings suggest that the strong inter-site exchange interactions in the
undoped islands are critical for the emergence of hourglass spectra in the
incommensurate magnetic phases of La2-xSrxCoO4.Comment: http://www.nature.com/articles/srep25117
Intricacies of the Co spin state in SrCoIrO: an x-ray absorption and magnetic circular dichroism study
We report on a combined soft x-ray absorption and magnetic circular dichroism
(XMCD) study at the Co- on the hybrid 3/5 solid state oxide
SrCoIrO with the KNiF structure. Our data
indicate unambiguously a pure high spin state for the Co
(3) ions with a significant unquenched orbital moment
despite the sizeable elongation of the CoO octahedra. Using quantitative
model calculations based on parameters consistent with our spectra, we have
investigated the stability of this high spin state with respect to the
competing low spin and intermediate spin states.Comment: 7 pages, 4 figure
-scaling and heat capacity in relativistic ion collisions
The -scaling method has been applied to the total multiplicity
distribution of the relativistic ion collisions of p+p, C+C and Pb+Pb which
were simulated by a Monte Carlo package, LUCIAE 3.0. It is found that the
-scaling parameter decreases with the increasing of the system size.
Moreover, the heat capacities of different mesons and baryons have been
extracted from the event-by-event temperature fluctuation in the region of low
transverse mass and they show the dropping trend with the increasing of impact
parameter.Comment: version 2: major change: 4 pages, 3 figures; Proceeding of
International Conference on "Strangeness in Quark Matter" (SQM2004), Cape
Town, South Africa, Spet. 2004 (Submitted to J. Phys. G.
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