3,119 research outputs found
Backflow and dissipation during the quantum decay of a metastable Fermi liquid
The particle current in a metastable Fermi liquid against a first-order phase
transition is calculated at zero temperature. During fluctuations of a droplet
of the stable phase, in accordance with the conservation law, not only does an
unperturbed current arise from the continuity at the boundary, but a backflow
is induced by the density response. Quasiparticles carrying these currents are
scattered by the boundary, yielding a dissipative backflow around the droplet.
An energy of the hydrodynamic mass flow of the liquid and a friction force
exerted on the droplet by the quasiparticles have been obtained in terms of a
potential of their interaction with the droplet.Comment: 5 pages (REVTeX), to be published in Phys. Rev.
Instability of a gapless color superconductor with respect to inhomogeneous fluctuations
We systematically apply density functional theory to determine the kind of
inhomogeneities that spontaneously develop in a homogeneous gapless phase of
neutral two-flavor superfluid quark matter. We consider inhomogeneities in the
quark and electron densities and in the phases and amplitude of the order
parameter. These inhomogeneities are expected to lead the gapless phase to a
BCS-normal coexisting phase, a Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) state
with phase oscillations alone, and a LOFF state with amplitude oscillations. We
find that which of them the homogeneous system tends towards depends
sensitively on the chemical potential separation between up and down quarks and
the gradient energies.Comment: 15 pages, 3 figures; corrected Eq. (36) and changed content
associated with d quark clustering instabilit
Activity measurement of solid Cu-In alloys by EMF method with solid electrolyte
The thermodynamic activity of indium in the solid Cu-In alloys was obtained from the EMF measurement of cell: In,In2O3, ZrO2(+11mol%CaO), Cu-In,In2O3 for 16 alloys in the temperature range 773 to 900K. Activity changes with composition at 823K are very large in the and - phase regions. Activity and free energies of formation are derived and compared with the published data
Coulomb Blockade with Dispersive Interfaces
What quantity controls the Coulomb blockade oscillations if the dot--lead
conductance is essentially frequency--dependent ? We argue that it is the ac
dissipative conductance at the frequency given by the effective charging
energy. The latter may be very different from the bare charging energy due to
the interface--induced capacitance (or inductance). These observations are
supported by a number of examples, considered from the weak and strong coupling
(perturbation theory vs. instanton calculus) perspectives.Comment: 4 page
Thermal Phase Transitions and Gapless Quark Spectra in Quark Matter at High Density
Thermal color superconducting phase transitions in three-flavor quark matter
at high baryon density are investigated in the Ginzburg-Landau (GL) approach.
We constructed the GL potential near the boundary with a normal phase by taking
into account nonzero quark masses, electric charge neutrality, and color charge
neutrality. We found that the density of states averaged over paired quarks
plays a crucial role in determining the phases near the boundary. By performing
a weak coupling calculation of the parameters characterizing the GL potential
terms of second order in the pairing gap, we show that three successive
second-order phase transitions take place as the temperature increases: a
modified color-flavor locked phase (ud, ds, and us pairings) -> a ``dSC'' phase
(ud and ds pairings) -> an isoscalar pairing phase (ud pairing) -> a normal
phase (no pairing). The Meissner masses of the gluons and the number of gapless
quark modes are also studied analytically in each of these phases.Comment: 15 pages, 6 figure
Influenced of Fe buffer thickness on the crystalline quality and the transport properties of Fe/Ba(Fe1-xCox)2As2 bilayers
The implementation of an Fe buffer layer is a promising way to obtain
epitaxial growth of Co-doped BaFe2As2 (Ba-122). However, the crystalline
quality and the superconducting properties of Co-doped Ba-122 are influenced by
the Fe buffer layer thickness, dFe. The well-textured growth of the Fe/Ba-122
bilayer with dFe = 15 nm results in a high Jc of 0.45 MAcm at 12 K in
self-field, whereas a low Jc value of 61000 Acm is recorded for the
bilayer with dFe = 4 nm at the corresponding reduced temperature due to the
presence of grain boundaries
Charmonium properties in deconfinement phase in anisotropic lattice QCD
J/Psi and eta_c above the QCD critical temperature T_c are studied in
anisotropic quenched lattice QCD, considering whether the c\bar c systems above
T_c are spatially compact (quasi-)bound states or scattering states. We adopt
the standard Wilson gauge action and O(a)-improved Wilson quark action with
renormalized anisotropy a_s/a_t =4.0 at \beta=6.10 on 16^3\times (14-26)
lattices, which correspond to the spatial lattice volume V\equiv
L^3\simeq(1.55{\rm fm})^3 and temperatures T\simeq(1.11-2.07)T_c. We
investigate the c\bar c system above T_c from the temporal correlators with
spatially-extended operators, where the overlap with the ground state is
enhanced. To clarify whether compact charmonia survive in the deconfinement
phase, we investigate spatial boundary-condition dependence of the energy of
c\bar c systems above T_c. In fact, for low-lying S-wave c \bar c scattering
states, it is expected that there appears a significant energy difference
\Delta E \equiv E{\rm (APBC)}-E{\rm (PBC)}\simeq2\sqrt{m_c^2+3\pi^2/L^2}-2m_c
(m_c: charm quark mass) between periodic and anti-periodic boundary conditions
on the finite-volume lattice. In contrast, for compact charmonia, there is no
significant energy difference between periodic and anti-periodic boundary
conditions. As a lattice QCD result, almost no spatial boundary-condition
dependence is observed for the energy of the c\bar c system in J/\Psi and
\eta_c channels for T\simeq(1.11-2.07)T_c. This fact indicates that J/\Psi and
\eta_c would survive as spatially compact c\bar c (quasi-)bound states below
2T_c. We also investigate a -wave channel at high temperature with maximally
entropy method (MEM) and find no low-lying peak structure corresponding to
\chi_{c1} at 1.62T_c.Comment: 13 pages, 11 figure
Neutrino emission from compact stars and inhomogeneous color superconductivity
We discuss specific heat and neutrino emissivity due to direct Urca processes
for quark matter in the color superconductive Larkin-Ovchinnikov-Fulde-Ferrell
(LOFF) phase of Quantum-Chromodynamics. We assume that the three light quarks
are in a color and electrically neutral state and interact by a four
fermion Nambu-Jona Lasinio coupling. We study a LOFF state characterized by a
single plane wave for each pairing. From the evaluation of neutrino emissivity
and fermionic specific heat, the cooling rate of simplified models of compact
stars with a quark core in the LOFF state is estimated.Comment: 16 pages, 5 figures, revtex4 style. Version accepted for publication
in Phys. Rev.
An Equation for the Vapor Pressure of Liquid Metals and Calculation of Their Enthalpies of Evaporation
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