11,902 research outputs found
Fermi-liquid effects in the Fulde-Ferrell-Larkin-Ovchinnikov state of two-dimensional d-wave superconductors
We study the effects of Fermi-liquid interactions on quasi-two-dimensional
d-wave superconductors in a magnetic field. The phase diagram of the
superconducting state, including the periodic Fulde-Ferrell-Larkin-Ovchinnikov
(FFLO) state in high magnetic fields, is discussed for different strengths of
quasiparticle many-body interactions within Landau's theory of Fermi liquids.
Decreasing the Fermi-liquid parameter causes the magnetic spin
susceptibility to increase, which in turn leads to a reduction of the FFLO
phase. It is shown that a negative results in a first-order phase
transition from the normal to the uniform superconducting state in a finite
temperature interval. Finally, we discuss the thermodynamic implications of a
first-order phase transition for CeCoIn.Comment: published version; removed direct comparison with experiment for the
upper critical field, as required by the referee
Force-Free Gravitational Redshift: Proposed Gravitational Aharonov-Bohm experiment
We propose a feasible laboratory interferometry experiment with matter waves
in a gravitational potential caused by a pair of artificial field-generating
masses. It will demonstrate that the presence of these masses (and, for moving
atoms, time dilation) induces a phase shift, even if it does not cause any
classical force. The phase shift is identical to that produced by the
gravitational redshift (or time dilation) of clocks ticking at the atom's
Compton frequency. In analogy to the Aharonov-Bohm effect in electromagnetism,
the quantum mechanical phase is a function of the gravitational potential and
not the classical forces.Comment: Updated to published versio
SDSSJ143244.91+301435.3 at VLBI: a compact radio galaxy in a narrow-line Seyfert 1
We present VLBI observations, carried out with the European Very Long
Baseline Interferometry Network (EVN), of SDSSJ143244.91+301435.3, a radio-loud
narrow-line Seyfert 1 (RLNLS1) characterized by a steep radio spectrum. The
source, compact at Very Large Array (VLA) resolution, is resolved on the
milliarcsec scale, showing a central region plus two extended structures. The
relatively high brightness temperature of all components (5x10^6-1.3x10^8 K)
supports the hypothesis that the radio emission is non-thermal and likely
produced by a relativistic jet and/or small radio lobes. The observed radio
morphology, the lack of a significant core and the presence of a low frequency
(230 MHz) spectral turnover are reminiscent of the Compact Steep Spectrum
sources (CSS). However, the linear size of the source (~0.5kpc) measured from
the EVN map is lower than the value predicted using the turnover/size relation
valid for CSS sources (~6kpc). This discrepancy can be explained by an
additional component not detected in our observations, accounting for about a
quarter of the total source flux density, combined to projection effects. The
low core-dominance of the source (CD<0.29) confirms that
SDSSJ143244.91+301435.3 is not a blazar, i.e. the relativistic jet is not
pointing towards the observer. This supports the idea that
SDSSJ143244.91+301435.3 may belong to the "parent population" of flat-spectrum
RLNLS1 and favours the hypothesis of a direct link between RLNLS1 and compact,
possibly young, radio galaxies.Comment: 8 pages, 3 figures, accepted for publication in MNRA
Interface enhancement of Gilbert damping from first-principles
The enhancement of Gilbert damping observed for Ni80Fe20 (Py) films in
contact with the non-magnetic metals Cu, Pd, Ta and Pt, is quantitatively
reproduced using first-principles scattering theory. The "spin-pumping" theory
that qualitatively explains its dependence on the Py thickness is generalized
to include a number of factors known to be important for spin transport through
interfaces. Determining the parameters in this theory from first-principles
shows that interface spin-flipping makes an essential contribution to the
damping enhancement. Without it, a much shorter spin-flip diffusion length for
Pt would be needed than the value we calculate independently
Islamic Banking Existence and Domestic Credit: Study at Seven Countries
This paper empirically investigates the determinants of domestic credit across a wide range of 7 countries; these are United Kingdom, Malaysia, Egypt, Kuwait, Qatar, Bahrain and Indonesia. We use dynamic panel estimation to examine effects of exchange rate, inflation, lending interest rate, banking crisis and existence of wholesale Islamic banking on domestic credit. We obtain several notable empirical results. First, the lending interest rate, banking crisis negatively and insignificantly contribute to domestic credit. The existence of Islamic bank has positive and insignificant contribution to domestic credit, while exchange rate positively and significantly contributes to domestic credit. Inflation negatively and significantly contributes to domestic credit. Second, banking crisis and existence of wholesale Islamic banking show insignificant effect on domestic credit. Third, we find that today\u27s domestic credit is depended on domestic credit in the previous year.DOI: 10.15408/aiq9i2.490
There are No Nice Interfaces in 2+1 Dimensional SOS-Models in Random Media
We prove that in dimension translation covariant Gibbs states
describing rigid interfaces in a disordered solid-on-solid (SOS) cannot exist
for any value of the temperature, in contrast to the situation in .
The prove relies on an adaptation of a theorem of Aizenman and Wehr.
Keywords: Disordered systems, interfaces, SOS-modelComment: 8 pages, gz-compressed Postscrip
There is no degree map for 0-cycles on Artin stacks
We show that there is no way to define degrees of 0-cycles on Artin stacks
with proper good moduli spaces so that (i) the degree of an ordinary point is
non-zero, and (ii) degrees are compatible with closed immersions.Comment: 3 page
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