V. V. Afonin

On the distributions of photoelectrons over the illuminated part of the moon

The existing view of the photoemission properties of lunar regolith does not provide the unambiguous treatment of the parameters and distributions of photoelectrons over the illuminated part of the Moon. This is indicated by the present calculations of the density, temperature, and distribution function of photoelectrons. It has been demonstrated that the quantum yield of lunar regolith is the main parameter determining the generation of photoelectrons near the surface of the Moon. At present, this parameter is determined with significant uncertainty. The measurement of the quantum yield of regolith directly on the surface of the Moon has been proposed as a variant of the solution of the indicated problem. Such measurements can be performed in the framework of future lunar missions.

Is weak temperature dependence of electron dephasing possible

The first-principle theory of electron dephasing by disorder-induced two state fluctuators is developed. There exist two mechanisms of dephasing. First, dephasing occurs due to direct transitions between the defect levels caused by inelastic electron-defect scattering. The second mechanism is due to violation of the time reversal symmetry caused by time-dependent fluctuations of the scattering potential. These fluctuations originate from an interaction between the dynamic defects and conduction electrons forming a thermal bath. The first contribution to the dephasing rate saturates as temperature decreases. The second contribution does not saturate, although its temperature dependence is rather weak,

BKT phase in systems of spinless strongly interacting one-dimensional fermions

\propto T^{1/3}

Luttinger liquid with one impurity: Equivalent field theory and duality

. The quantitative estimates based on the experimental data show that these mechanisms considered can explain the weak temperature dependence of the dephasing rate in some temperature interval. However, below some temperature dependent on the model of dynamic defects the dephasing rate tends rapidly to zero. The relation to earlier studies of the dephasing caused by the dynamical defects is discussed.

Exchange Fluctuations in a Nonequilibrium Lorentz Gas

We present the ground-state wavefunctions for a system of spinless one-dimensional fermions in the limit of an infinitely strong interaction, and we demonstrate explicitly that the system symmetry is lower than the original symmetry of the Hamiltonian. As a result, the system in this limit undergoes a second-order phase transition into a phase with finite density of chiral pairs. The phase transforms continuously into a Berezinskii-Kosterlitz-Thouless (BKT) phase if the interaction in the model decreases. Therefore, just the BKT phase is realized in nature. The temperature of the smearing phase transition is calculated.

One-dimensional strongly interacting electrons with a single impurity: Conductance reemergence

We derive by functional integral method one-dimensional theory equivalent to Luttinger liquid with one impurity. It is shown that the single quantity has to be calculated for the formulation the effective field theory is the electron density jump at the impurity. We show that duality which relates models with electron-electron attraction and repulsion, and simultaneous exchange of transition and reflection coefficients, is an exact property of the theory.

Spontaneous symmetry breaking in a system of strongly interacting multicomponent fermions (electrons with spin and conducting nanotubes)

It has been shown that a correlation mechanism that is based on the exchange interaction and destroys the relation between distribution functions and response (Price relation) occurs in a nonequilibrium Lorentz gas (particles interact only with the thermostat). The physical nature of this phenomenon is that the scattering of particles of the gas in the same state on a single particle of the thermostat creates a flux of correlated pairs, which depends on the form of a nonequilibrium distribution function, making impossible the existence of a universal relation between distribution functions and response.

Magnetization of a diffusive ring: Beyond the perturbation theory

We show that the conductance of a 1D channel with one point-like impurity critically depends on the asymptotic behavior of the e-e interaction at low momenta k (about the inverse length of the channel). The conductance reemerges (contrary to the case of a point-like repulsive potential) if the potential satisfies the condition V (k = 0) = 0. For example, this happens if the bare e-e interaction is screened by the charges in the bulk. The relation of this phenomenon to the long-range order present in the Luttinger model is discussed. We consider spinless electrons but generalization is straightforward.

On the anomalous transparency of superconductors

We calculate the ground-state wave functions for a system of multicomponent strongly interacting fermions. We show that it is a state with spontaneously broken chiral symmetry that describes a phase with a finite density of chiral complexes. The number of particles constituting a complex depends on the number of fermion components. For example, in the case of two-component electrons (spin), the condensate is built of four-particle complexes consisting of two “right” electrons and two “left” holes with the opposite spins.

On the absorption of a surface acoustic wave in a bulk superconductor in the presence of a supercurrent

Average persistent current over a set of diffusive metallic rings with fixed number of electrons is considered. We study the case in which the phase breaking time is much greater than an inverse average interlevel distance. In such a case, many return events for an electron must be taken into account. As a result, one arrives at a nonperturbative problem for a cooperon mode fixed by an external magnetic field. This multi-cooperon problem has been considered previously by Altland et al., [Europhys. Lett. 20, 155 (1992)] and in several following papers within the framework of supersymmetric approach. Such an approach involves very tedious calculations which were performed using a computer algebraic package. Here we solve the problem in question with the help of a replica trick. It is demonstrated that the replica trick in combination with a proper analytical continuation in the replica space allows one to obtain the result in much more explicit way.