FIELD-ASYMMETRIC TRANSVERSE MAGNETORESISTANCE IN A NONMAGNETIC QUANTUM-SIZE STRUCTURE

A new phenomenon is observed experimentally in a heavily doped asymmet ric quantum-size structure in a magnetic field parallel to the quantum -well layers - a transverse magnetoresistance which is asymmetric in t he field (there can even be a channge in sign) and is observed in the case that the structure has a built-in lateral electric field. A model of the effect is proposed. The observed asymmetry of the magnetoresis tance is attributed to an additional current contribution that arises under nonequilibrium conditions and that is linear in the gradient of the electrochemical potential and proportional to the parameter charac terizing the asymmetry of the spectrum with respect to the quasimoment um. (C) 1998 American Institute of Physics. [S0021-3640(98)00617-3].