182 research outputs found
Energy losses of fast heavy-ion projectiles in dense hydrogen plasmas
It has been recently shown that the Bethe-Larkin formula for the energy
losses of fast heavy-ion projectiles in dense hydrogen plasmas is corrected by
the electron-ion correlations [Phys. Rev. Lett. \textbf{101}, 075002 (2008)].
We report numerical estimates of this correction based on the values of
obtained by numerical simulations in [Phys. Rev. E \textbf{61},
3470 (2000)]. We also extend this result to the case of projectiles with
dicluster charge distribution. We show that the experimental visibility of the
electron-ion correlation correction is enhanced in the case of dicluster
projectiles with randomly orientated charge centers. Although we consider here
the hydrogen plasmas to make the effect physically more clear, the
generalization to multispecies plasmas is straightforward.Comment: 5 pages, 1 figure. International Conference on Strongly Coupled
Coulomb Systems 2008, Camerino (Italy). To appear in J. Phys.
Lattice thermal conductivity of graphene with conventionally isotopic defects
The thermal conductivity of doped graphene flake of finite size is
investigated with emphasis on the influence of mass of substituting atoms on
this property. It is shown that the graphene doping by small concentrations of
relatively heavy atoms results in a disproportionately impressive drop of
lattice thermal conductivity.Comment: 12 pages, 3 figure
Linear, diatomic crystal: single-electron states and large-radius excitons
The large-radius exciton spectrum in a linear crystal with two atoms in the
unit cell was obtained using the single-electron eigenfunctions and the band
structure, which were found by the zero-range potential (ZRP) method. The
ground-state exciton binding energies for the crystal in vacuum appeared to be
larger than the corresponding energy gaps for any set of the crystal
parameters.Comment: 9 pages, 1 figure, 1 tabl
Fast projectile stopping power of quantal multi-component strongly coupled plasmas
The Bethe-Larkin formula for the fast projectile stopping power is extended
to multi-component plasmas. The results are to contribute to the correct
interpretation of the experimental data, which could permit to test the
existing and future models of thermodynamic, static, and dynamic
characteristics of strongly coupled Coulomb systems.Comment: 4 pages, to appear in PR
Collective and static properties of model two-component plasmas
Classical MD data on the charge-charge dynamic structure factor of
two-component plasmas (TCP) modeled in Phys. Rev. A 23, 2041 (1981) are
analyzed using the sum rules and other exact relations. The convergent power
moments of the imaginary part of the model system dielectric function are
expressed in terms of its partial static structure factors, which are computed
by the method of hypernetted chains using the Deutsch effective potential.
High-frequency asymptotic behavior of the dielectric function is specified to
include the effects of inverse bremsstrahlung. The agreement with the MD data
is improved, and important statistical characteristics of the model TCP, such
as the probability to find both electron and ion at one point, are determined.Comment: 25 pages, 6 figures, 5 tables. Published in Physical Review E
http://link.aps.org/abstract/PRE/v76/e02640
Large radius exciton in single-walled carbon nanotubes
The spectrum of large radius exciton in an individual semiconducting
single-walled carbon nanotube (SWCNT) is described within the framework of
elementary potential model, in which exciton is modeled as bound state of two
oppositely charged quasi-particles confined on the tube surface. Due to the
parity of the interaction potential the exciton states split into the odd and
even series. It is shown that for the bare and screened Coulomb electron-hole
(e-h) potentials the binding energy of even excitons in the ground state well
exceeds the energy gap. The factors preventing the collapse of single-electron
states in isolated semiconducting SWCNTs are discussed.Comment: 14 pages, 1 figure, 5 table
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