13,283 research outputs found
Electromagnetic surface modes in a magnetized quantum electron-hole plasma
The propagation of surface electromagnetic waves along a uniform magnetic
field is studied in a quantum electron-hole semiconductor plasma. A new forward
propagating mode, not reported before, is found by the effect of quantum
tunneling, which otherwise does not exist. In the classical limit
() one of the low-frequency modes is found similar to an
experimentally observed one in -type InSb at room temperature. The surface
modes are shown to be significantly modified in the case of high-conductivity
semiconductor plasmas where electrons and holes may be degenerate. The effects
of the external magnetic field and the quantum tunneling on the surface wave
modes are discussed.Comment: 4 pages, 3 figures; to appear in Phys. Rev. E (2011
Length and time scale divergences at the magnetization-reversal transition in the Ising model
The divergences of both the length and time scales, at the magnetization-
reversal transition in Ising model under a pulsed field, have been studied in
the linearized limit of the mean field theory. Both length and time scales are
shown to diverge at the transition point and it has been checked that the
nature of the time scale divergence agrees well with the result obtained from
the numerical solution of the mean field equation of motion. Similar growths in
length and time scales are also observed, as one approaches the transition
point, using Monte Carlo simulations. However, these are not of the same nature
as the mean field case. Nucleation theory provides a qualitative argument which
explains the nature of the time scale growth. To study the nature of growth of
the characteristic length scale, we have looked at the cluster size
distribution of the reversed spin domains and defined a pseudo-correlation
length which has been observed to grow at the phase boundary of the transition.Comment: 9 pages Latex, 3 postscript figure
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