Volume 35, Issue 5, May 2009
Index of content:
- LOW-DIMENSIONAL AND DISORDERED SYSTEMS
35(2009); http://dx.doi.org/10.1063/1.3132746View Description Hide Description
The large-radius exciton spectrum in a linear crystal with two atoms in the unit cell is obtained using the single-electron eigenfunctions and band structure found by the zero-range potentials method. The ground-state exciton binding energies for the linear crystal in vacuum turn out to be larger than the corresponding energy gaps for any set of the crystal parameters.
35(2009); http://dx.doi.org/10.1063/1.3132748View Description Hide Description
The equivalence is established between a one-dimensional (1D) Bose system with a finite number of particles and a system obeying fractional (intermediate) Gentile statistics, in which the maximum occupation of single-particle energy levels is limited. A system of 1D harmonic oscillators, providing a model for a harmonically trapped Bose gas, is considered. The results are generalized for a system with a power-law energy spectrum.
35(2009); http://dx.doi.org/10.1063/1.3132749View Description Hide Description
The conductivity of a two-dimensional electron system with surface density and above a liquid-heliumsurface is investigated near a phase transition into the crystalline state (Wigner crystal). The measurements are performed in the frequency range for different amplitudes of a guiding field. The phase transition was detected according to a sharp change of the amplitude and phase of the response signal. The temperature dependences of the real and imaginary components of the conductivity of two-dimensional system of electrons and the melting temperature are calculated. It is found that the temperature dependences of the imaginary part of the reciprocal of the conductivity, which reflect the inertial properties of the electron system, match well for different frequencies of the exciting signal, while the real component, which characterizes dissipation, increases with increasing frequency at the transition into an ordered state. It is found that at the transition into an ordered state both components of the reciprocal of the conductivity increase with increasing guiding electric field.