Optical phonon–assisted magnetotunneling peaks inGaAs/AlxGa1−xAsdouble-barrier structures

Abstract

The effect of the interface optical (IO) phonons and the confined LO phonons in a ${\mathrm{Al}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{As}$ emitter barrier and GaAs quantum well on the phonon-assisted tunneling through a double-barrier structure has been studied in the presence of a magnetic field in the direction of the current. The tunneling current densities are calculated and the numerical results for the typical ${\mathrm{G}\mathrm{a}\mathrm{A}\mathrm{s}/\mathrm{A}\mathrm{l}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{As}$ structures are given graphically. An alternative recognition of the phonon-assisted tunneling current peaks is suggested. Only one theoretical peak from the IO phonons and the confined LO phonons is easy to be observed for wide well systems. The second peak appears at the position corresponding to the emission of the confined higher-frequency branch LO phonon in the ternary mixed-crystal emitter barrier and can also be observed in the narrower-well systems.