138 research outputs found
Finite temperature effects in antiferromagnetism of nuclear matter
The influence of the finite temperature on the antiferromagnetic (AFM) spin
ordering in symmetric nuclear matter with the effective Gogny interaction is
studied within the framework of a Fermi liquid formalism. It is shown that the
AFM spin polarization parameter of partially polarized nuclear matter for low
enough temperatures increases with temperature. The entropy of the AFM spin
state for some temperature range is larger than the entropy of the normal
state. Nerveless, the free energy of the AFM spin state is always less than the
free energy of the normal state and, hence, the AFM spin polarized state is
preferable for all temperatures below the critical temperature.Comment: To appear in PRC; some references and comments adde
Spin polarized states in neutron matter at a strong magnetic field
Spin polarized states in neutron matter at a strong magnetic field are
considered in the model with the Skyrme effective interaction (SLy4, SLy7
parametrizations). Analyzing the self-consistent equations at zero temperature,
it is shown that a thermodynamically stable branch of solutions for the spin
polarization parameter as a function of density corresponds to the negative
spin polarization when the majority of neutron spins are oriented oppositely to
the direction of the magnetic field. Besides, beginning from some threshold
density being dependent on the magnetic field strength the self-consistent
equations have also two other branches (upper and lower) of solutions for the
spin polarization parameter with the positive spin polarization.
The free energy corresponding to the upper branch turns out to be very close
to the free energy corresponding to the thermodynamically preferable branch
with the negative spin polarization. As a consequence, at a strong magnetic
field, the state with the positive spin polarization can be realized as a
metastable state at the high density region in neutron matter which under
decreasing density at some threshold density changes into a thermodynamically
stable state with the negative spin polarization. The calculations of the
neutron spin polarization parameter and energy per neutron as functions of the
magnetic field strength show that the influence of the magnetic field remains
small at the field strengths up to G.Comment: Prepared with RevTeX4, 8pp., 5 figs; v.2: matches published versio
Unusual temperature behavior of entropy of antiferromagnetic spin state in nuclear matter with effective finite range interaction
The unusual temperature behavior of the entropy of the antiferromagnetic
(AFM) spin state in symmetric nuclear matter with the Gogny D1S interaction,
being larger at low temperatures than the entropy of nonpolarized matter, is
related to the dependence of the entropy on the effective masses of nucleons in
a spin polarized state. The corresponding conditions for comparing the
entropies of the AFM and nonpolarized states in terms of the effective masses
are formulated, including low and high temperature limits. It is shown that the
unexpected temperature behavior of the entropy of the AFM spin state at low
temperatures is caused by the violation of the corresponding low temperature
criterium.Comment: version accepted for publication in PR
Phase transition to the state with nonzero average helicity in dense neutron matter
The possibility of the appearance of the states with a nonzero average
helicity in neutron matter is studied in the model with the Skyrme effective
interaction. By providing the analysis of the self-consistent equations at zero
temperature, it is shown that neutron matter with the Skyrme BSk18 effective
force undergoes at high densities a phase transition to the state in which the
degeneracy with respect to helicity of neutrons is spontaneously removed.Comment: 4 pages, 3 figures; v2: journal versio
Spin polarized states in strongly asymmetric nuclear matter
In the framework of a Fermi liquid theory it is considered the possibility of
appearance of spin polarized states in strongly asymmetric nuclear matter with
Skyrme effective interaction. The zero temperature dependence of neutron and
proton spin polarization parameters as functions of density is found for SLy4,
SLy5 effective forces. It is shown that at some critical density it will be
formed the state with the oppositely directed spins of neutrons and protons,
while the state with the same direction of spins does not appear. In comparison
with neutron matter, even small admixture of protons strongly decreases the
threshold density of spin instability. It is clarified that protons become
totally polarized within very narrow density domain while in the density
profile of neutron spin polarization parameter their appear long tails near the
transition density.Comment: Prepared with RevTeX4, 8p., 3 figures; to appear in PR
Anisotropic multi-gap superfluid states in nuclear matter
It is shown that under changing density or temperature a nucleon Fermi
superfluid can undergo a phase transition to an anisotropic superfluid state,
characterized by nonvanishing gaps in pairing channels with singlet-singlet
(SS) and triplet-singlet (TS) pairing of nucleons (in spin and isospin spaces).
In the SS pairing channel nucleons are paired with nonzero orbital angular
momentum. Such two-gap states can arise as a result of branching from the
one-gap solution of the self-consistent equations, describing SS or TS pairing
of nucleons, that depends on the relationship between SS and TS coupling
constants at the branching point. The density/temperature dependence of the
order parameters and the critical temperature for transition to the anisotropic
two-gap state are determined in a model with the SkP effective interaction. It
is shown that the anisotropic SS-TS superfluid phase corresponds to a
metastable state in nuclear matter.Comment: Prepared with RevTeX4, 7p., 5 fi
TRANSFER OF ELECTRIC CHARGE THROUGH Al-Se95Te5-Te STRUCTURE
It is established that current passing through Al-Se95Te5<Sm>-Te structures is carried out by monopolar injection mechanism at participation of traps for holes. It is shown that the doping by samarium strongly influences on the current flow mechanism in the investigated structure due to changes in the energy spectrum of the local states.The local level parameters (concentration and energy state) controlling the electric charge transfer are defined with the use of existing theories of injection currents
The application of legal-statistical method in analysing manufacturing property’s institutional development
Purpose: The study defines the specifics and opportunities, that arise due to the application of statistical method in judicial research of manufacturing property. Design/Methodology/Approach: The authors put the ground of the study on the aggregation of a vast spectrum of statistical data and indicators of patent activity of leading countries in the sphere of technological innovation. Findings: The authors outlined the main tendencies of legal regulation of scientific and artistic results of intellectual property development and define the specifics and opportunities that arise due to the application of statistical method in judicial research of manufacturing property. Lack of coordination of approaches to protect manufacturing property on the international level, obstructs the development of patent activity amongst the members of the Paris Convention and significantly reduces the effectiveness of the current patent system. Practical implications: Authors' development could be utilized in future developments of Russian institute of manufacturing property and its legal framework. Originality/Value: The contribution of the article is the comprehensive analysis of legal background of intellectual property institute and its development prospects.peer-reviewe
- …