Vol 108, No 10 (2018)

We calculate the frequency-dependent shot noise in the edge states of a two-dimensional topological insulator coupled to a magnetic impurity with spin S = 1/2 of arbitrary anisotropy. If the anisotropy is absent, the noise is purely thermal at low frequencies, but tends to the Poisson noise of the full current I at high frequencies. If the interaction only flips the impurity spin but conserves those of electrons, the noise at high voltages eV ≫ T is frequency-independent. Both the noise and the backscattering current I_bs saturate at voltageindependent values. Finally, if the Hamiltonian contains all types of non-spin-conserving scattering, the noise at high voltages becomes frequency-dependent again. At low frequencies, its ratio to 2eI_bs is larger than 1 and may reach 2 in the limit I_bs→0. At high frequencies, it tends to 1.

We propose the new nondissipative transport effect—the appearance of axial current of thermal quasiparticles in the presence of background gravity with torsion. For the non-interacting model of massless Dirac fermions, the response of the axial current to torsion is derived. The chiral vortical effect appears to be the particular case of the chiral torsional effect. The proposed effect may be observed in the condensed matter systems with emergent relativistic invariance (Weyl/Dirac semimetals and the ³He-A superfluid).

Features of the aggregation of С₇₀ fullerene in an o-xylol have been revealed by observing the Doppler shift as a nondiffusive component in the dynamic light scattering spectra. The Doppler shift is proportional to the intensity of the incident light flux. This indicates the entrainment of formed aggregates by a laser beam and is consistent with the concept of the pressure of electromagnetic radiation, in particular, light.

We continue to develop our method for effectively computing the special Kähler geometry on the moduli space of Calabi–Yau manifolds. We generalize it to all polynomial deformations of Fermat hypersurfaces.

In the present paper, we discuss the eigenvalue conjecture, suggested in 2012, in the particular case of U_q(sl_N) 6-j The eigenvalue conjecture provides a certain symmetry for Racah coefficients and we prove that the eigenvalue conjecture is provided by the Regge symmetry for U_q(sl_N) 6-j, when three representations coincide. This in perspective provides us a kind of generalization of the Regge symmetry to arbitrary U_q(sl_N) 6-j.

A pronounced quadrupole emission effect is theoretically predicted in terms of the contact interaction operator in resonant inelastic scattering of two X-ray photons near the ionization threshold energy of the 1s shell of a free multielectron atom. The observed double differential scattering cross section is estimated quantitatively.

A nonideal helium plasma has been compressed to a density of ~9 g/cm³ by a pressure of P ~ 10000 GPa produced by an explosive charge of 85 kg of TNT in a spherical two-cascade device. The experiment has been performed on an X ray setup using simultaneously three betatrons with a boundary energy of about 60 MeV and a multichannel optoelectronic system of recording X-ray images. The pressure of the compressed helium has been determined from the gas-dynamic calculation.

Studies of the scattering of light on systems of identical atoms under conditions of their quantum degeneracy have been reviewed. The formation of a periodic spatial structure caused by the interference of material waves is responsible for coherent resonance scattering similar to Bragg diffraction on regular spatial inhomogeneities. The interference of macroscopic material waves that is observed in experiments with a Bose–Einstein condensate forms a dielectric medium in the region of optical transparency of the sample that has the properties of a photonic crystal. Common characteristics and differences between the scattering of light on atomic systems under quantum degeneracy conditions and scattering on one-dimensional atomic lattices where the positions of atoms are described by classical statistics have been discussed.