arXiv subjects

S. A. Vitkalov

Publications and source records attributed to S. A. Vitkalov.

22 records · Page 2Linked to original sources

arXiv2000

Temperature-Dependence of the Resistivity of a Dilute 2D Electron System in High Parallel Magnetic Field

We report measurements of the resistance of silicon MOSFETs as a function of temperature in high parallel magnetic fields where the 2D system of electrons has been shown to be fully spin-polarized. A magnetic field suppresses the metallic behavior observed in the absence of a magnetic field. In a field of 10.8 T, insulating behavior is found for densities up to n_s approximately 1.35 x 10^{11} cm^{-2} or 1.5 n_c; above this density the resistance is a very weak function of temperature, varying less than 10% between 0.25 K and 1.90 K. At low densities the resistance goes to infinity more rapidly as the temperature is reduced than in zero field and the magnetoresistance diverges as T goes to 0.

cond-mat.str-el↗

arXiv2000

Hall Coefficient of a Dilute 2D Electron System in Parallel Magnetic Field

Measurements in magnetic fields applied at a small angle with respect to the 2D plane of the electrons of a low-density silicon MOSFET indicate that the Hall coefficient is independent of parallel field from H=0 to $H>H_{sat}$, the field above which the longitudinal resistance saturates and the electrons have reached full spin-polarization. This implies that the mobilities of the spin-up and spin-down electrons remain comparable at all magnetic fields, and suggests there is strong mixing of spin-up and spin-down electron states.

cond-mat.str-el↗

arXiv1999

Sharp Transition to a Spin-Ordered Phase in the 2D Electron System in Silicon MOSFET's

This paper has been withdrawn by the authors. Measurements at many different angles spanning a broad range of electron densities indicate that the observed doubling of the period of Shubnikov-de Haas oscillations, which we had attributed to a transition to a new spin-ordered phase, is also consistent with an alternative explanation. A full interpretation of our data will be posted at a later date.

cond-mat.str-el↗

arXiv1998

Vortex Drag in Quantum Hall Effect

A new model of momentum and electric field transfer between two adjacent 2D electron systems in the Quantum Hall Effect is proposed. The drag effect is due to momentum transfer from the vortex system of one layer to the vortex system of another layer. The remarkable result of this approach is periodical change of $sign$ of the dragged electric field with difference between the layer filling factors.

cond-mat.mes-hall↗