Nonlinear transport in a two-dimensional electron gas with a periodically modulated potential

Article

关键词: NEGATIVE DIFFERENTIAL CONDUCTIVITY;    SEMICONDUCTOR SUPERLATTICES;    BLOCH OSCILLATIONS;    MINIBAND;    EMISSION;    CARRIERS;   

DOI  :  10.1103/PhysRevB.84.195320

来源: SCIE

【 摘 要 】

We study the nonlinear response of the current of a two-dimensional electron gas with a periodically modulated potential in one direction in a strong DC electric field at low temperatures. The dependence of the current on the field, the electron density, and the temperature is investigated by using a relaxation-time approximation for inelastic scattering. Elastic scattering is treated microscopically including interband scattering. The roles of elastic and inelastic scattering on the nonlinear current are examined. The result is applied to the Kronig-Penney model. It is found that, for a fixed total scattering rate, the field dependence of the current is insensitive to the ratio of the elastic and inelastic scattering rates in contrast with the recent results of the nonlinear current of similar models of a single miniband in one dimension and three dimensions. The result from the Kronig-Penney model is compared with the recent data from a modulated two-dimensional GaAs quantum well which show evidence of the negative differential conductance.

【 授权许可】

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