RESUMEN
Electromagnetic instability criteria in semiconductor superlattices (SL) in the region of a negative differential conductivity (NDC) are studied in the presence of a static transverse field. The regimes with vertical constant electric field in a "short" plate of SL and with vertical current density vector in a "long" plate are considered. The effective differential conductivity tensors for both these regimes are derived and the influence of the magnetic field on the NDC threshold and the growth increment is investigated. The frequencies of the excited waves and the dependence of the growth increment on the direction of propagation for the extraordinary waves are determined.
Asunto(s)
Cristalización/métodos , Campos Electromagnéticos , Modelos Químicos , Nanoestructuras/química , Nanoestructuras/efectos de la radiación , Semiconductores , Simulación por Computador , Relación Dosis-Respuesta en la Radiación , Conductividad Eléctrica , Dosis de RadiaciónRESUMEN
It is shown that in semiconductor superlattices surface electromagnetic waves traveling in the direction parallel to the external static electric field may become unstable. This instability manifests itself in the emission of electromagnetic waves. The instability criteria are derived, and the frequency as well as the growth increment and the direction of the emitted waves are determined.