Hopping conductivity in heavily doped n-type GaAs layers in the quantum Hall effect regime

We investigate the magnetoresistance of epitaxially grown, heavily doped n-type GaAs layers with thickness (40-50 nm) larger than the electronic mean free path (23 nm). The temperature dependence of the dissipative resistance R_{xx} in the quantum Hall effect regime can be well described by a hopping law (R_{xx} \propto exp{-(T_0/T)^p}) with p=0.6. We discuss this result in terms of variable range hopping in a Coulomb gap together with a dependence of the electron localization length on the energy in the gap. The value of the exponent p>0.5 shows that electron-electron interactions have to be taken into account in order to explain the occurrence of the quantum Hall effect in these samples, which have a three-dimensional single electron density of states.Comment: 5 pages, 2 figures, 1 tabl

Quantum Hall Effect induced by electron-electron interaction in disordered GaAs layers with 3D spectrum

It is shown that the observed Quantum Hall Effect in epitaxial layers of heavily doped n-type GaAs with thickness (50-140 nm) larger the mean free path of the conduction electrons (15-30 nm) and, therefore, with a three-dimensional single-particle spectrum is induced by the electron-electron interaction. The Hall resistance R_xy of the thinnest sample reveals a wide plateau at small activation energy E_a=0.4 K found in the temperature dependence of the transverse resistance R_xx. The different minima in the transverse conductance G_xx of the different samples show a universal temperature dependence (logarithmic in a large range of rescaled temperatures T/T_0) which is reminiscent of electron-electron-interaction effects in coherent diffusive transport.Comment: 6 pages, 3 figures, 1 tabl

On the Phase Boundaries of the Integer Quantum Hall Effect. II

It is shown that the statements about the observation of the transitions between the insulating phase and the integer quantum Hall effect phases with the quantized Hall conductivity $\sigma_{xy}^{q}$ $\geq 3e^{2}/h$ made in a number of works are unjustified. In these works, the crossing points of the magnetic field dependences of the diagonal resistivity at different temperatures at $\omega_{c}\tau \approx 1$ have been misidentified as the critical points of the phase transitions. In fact, these crossing points are due to the sign change of the derivative $d\rho_{xx}/dT$ owing to the quantum corrections to the conductivity.Comment: 3 pages, 2 figure

The effect of the relative nuclear size on the nucleus-nucleus interactions

The experimental data on the interactions of light nuclei (d, He(4), C(12)) at the momentum 4.2 GeV/cA with the carbon nuclei were taken in the 2-m propane bubble chamber. The distributions in the number of interacting nucleons, the spectra of protons, the mean energies of secondary pions and protons, the mean fractions of energy transferred to the pion and nucleon components are presented. The results of the investigation of the mechanism of nucleus-nucleus interactions can be used to calculate the nuclear cascades in the atmosphere

Universal flow diagram for the magnetoconductance in disordered GaAs layers

The temperature driven flow lines of the diagonal and Hall magnetoconductance data (G_{xx},G_{xy}) are studied in heavily Si-doped, disordered GaAs layers with different thicknesses. The flow lines are quantitatively well described by a recent universal scaling theory developed for the case of duality symmetry. The separatrix G_{xy}=1 (in units e^2/h) separates an insulating state from a spin-degenerate quantum Hall effect (QHE) state. The merging into the insulator or the QHE state at low temperatures happens along a semicircle separatrix G_{xx}^2+(G_{xy}-1)^2=1 which is divided by an unstable fixed point at (G_{xx},G_{xy})=(1,1).Comment: 10 pages, 5 figures, submitted to Phys. Rev. Let

Educar los enfoques de la propiedad intelectual como tendencias de aplicación de la buena fe subjetiva en el derecho ruso

In Russian law, the term "good faith" ("good conscience") refers to different concepts: "honest practice" and "ignorance of the fact when such ignorance generates legal consequences." The article investigate  the educational aspects of distinguishing  objective and subjective good faith. The questions of application of the rules on subjective good faith to the relations arising in connection with the establishment, circulation and protection of civil rights are considered. The analysis of the content of the legal regime of objects of absolute property rights (things, property security, share in the right of common property, corporate rights) allowed us to conclude that the consideration of the rules on subjective good faith is a natural, necessary element of the legal regime of any object of civil turnover, and the real question is only the recognition of such an element of the legal regime by the rule of law and the definition of the features of its application.En la ley rusa, el término "buena fe" ("buena conciencia") se refiere a diferentes conceptos: "práctica honesta" e "ignorancia del hecho cuando tal ignorancia genera consecuencias legales". El artículo investiga los aspectos educativos de distinguir la buena fe objetiva y subjetiva. Se consideran las cuestiones de aplicación de las normas sobre buena fe subjetiva a las relaciones que surgen en relación con el establecimiento, la circulación yla protección de los derechos civiles. El análisis del contenido del régimen legal de los objetos de derechos de propiedad absolutos (cosas, seguridad de la propiedad, participación en el derecho de propiedad común, derechos corporativos) nos permitió concluir que la consideración de las reglas sobre la buena fe subjetiva es algo natural, elemento necesario del régimen legal de cualquier objeto de renovación civil, y la cuestión real es solo el reconocimiento de dicho elemento del régimen legal por el estado de derecho y la definición de las características de su aplicación

Tendencias de aplicación de la buena fe subjetiva en el derecho ruso: enfoques de propiedad intelectual

In Russian law, the term “good faith” (“good conscience”) refers to different concepts: “honest practice” and “ignorance of the fact when such ignorance generates legal consequences.” The article distinguishes between objective and subjective good faith. The questions of application of the rules on subjective good faith to the relations arising in connection with the establishment, circulation and protection of civil rights are considered. The analysis of the content of the legal regime of objects of absolute property rights (things, property security, share in the right of common property, corporate rights) allowed us to conclude that the consideration of the rules on subjective good faith is a natural, necessary element of the legal regime of any object of civil turnover, and the real question is only the recognition of such an element of the legal regime by the rule of law and the definition of the features of its application.En la ley rusa, el término «buena fe» («buena conciencia») se refiere a diferentes conceptos: «práctica honesta» e «ignorancia del hecho cuando tal ignorancia genera consecuencias legales». El artículo distingue entre buena fe objetiva y subjetiva. Se consideran las cuestiones de aplicación de las normas sobre la buena fe subjetiva a las relaciones que surgen en relación con el establecimiento, la circulación y la protección de los derechos civiles. El análisis del contenido del régimen legal de los objetos de derechos de propiedad absolutos (cosas, seguridad de la propiedad, participación en el derecho de propiedad común, derechos corporativos) nos permitió concluir que la consideración de las reglas sobre la buena fe subjetiva es algo natural, elemento necesario del régimen legal de cualquier objeto de renovación civil, y la cuestión real es solo el reconocimiento de dicho elemento del régimen legal por el estado de derecho y la definición de las características de su aplicación