335 research outputs found
Two-instanton approximation to the Coulomb blockade problem
We develop the two-instanton approximation to the current-voltage
characteristic of a single electron transistor within the
Ambegaokar-Eckern-Sch\"on model. We determine the temperature and gate voltage
dependence of the Coulomb blockade oscillations of the conductance and the
effective charge. We find that a small (in comparison with the charging energy)
bias voltage leads to significant suppression of the Coulomb blockade
oscillations and to appearance of the bias-dependent phase shift
Energy relaxation in the spin-polarized disordered electron liquid
The energy relaxation in the spin-polarized disordered electron systems is
studied in the diffusive regime. We derived the quantum kinetic equation in
which the kernel of electron-electron collision integral explicitly depends on
the electron magnetization. As the consequence, the inelastic scattering rate
is found to have non-monotonic dependence on the spin polarization of the
electron system
Renormalization of hole-hole interaction at decreasing Drude conductivity
The diffusion contribution of the hole-hole interaction to the conductivity
is analyzed in gated GaAs/InGaAs/GaAs heterostructures. We show
that the change of the interaction correction to the conductivity with the
decreasing Drude conductivity results both from the compensation of the singlet
and triplet channels and from the arising prefactor in the
conventional expression for the interaction correction.Comment: 6 pages, 5 figure
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.
On the effect of far impurities on the density of states of two-dimensional electron gas in a strong magnetic field
The effect of impurities situated at different distances from a
two-dimensional electron gas on the density of states in a strong magnetic
field is analyzed. Based on the exact result of Brezin, Gross, and Itzykson, we
calculate the density of states in the whole energy range, assuming the Poisson
distribution of impurities in the bulk. It is shown that in the case of small
impurity concentration the density of states is qualitatively different from
the model case when all impurities are located in the plane of the
two-dimensional electron gas.Comment: 6 pages, 1 figure, submitted to JETP Letter
- …