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تسجيل مستخدم جديدThe Hall effect in ballistic flow of two-dimensional interacting particles
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In high-quality solid-state systems at low temperatures, the hydrodynamic or the ballistic regimes of heat and charge transport are realized in the electron and the phonon systems. In these regimes, the thermal and the electric conductance of the sample can reach abnormally large magnitudes. In this paper, we study the Hall effect in a system of interacting two-dimensional charged particles in a ballistic regime. We demonstrated that the Hall electric field is caused by a change in the densities of particles due to the effect of external fields on their free motions between the sample edges. In one-component (electron or hole) systems the Hall coefficient turns out to one half compared with the one in conventional disordered Ohmic samples. This result is consistent with the recent experiment on measuring of the Hall resistance in ultra-high-mobility GaAs quantum wells. In two-component electron-hole systems the Hall electric field depends linearly on the difference between the concentrations of electrons and holes near the charge neutrality point (the equilibrium electron and hole densities coincide) and saturates to the Hall field of a one-component system far from the charge neutrality point. We also studied the corrections to magnetoresistance and the Hall electric field due to inter-particle scattering being a precursor of forming a viscous flow. For the samples shorter than the inter-particle scattering length, the obtained corrections govern the dependencies of magnetoresistance and the Hall field on temperature.
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