TRANSMISSION COEFFICIENTS FOR RESONANT-TUNNELING IN MULTIBARRIER GRADED QUANTUM-WELL SEMICONDUCTOR HETEROSTRUCTURES

Resonant tunneling of electrons is studied in a new class of multi-bar rier semiconductor heterostructures which contain graded quantum wells , whose slopes can be changed by varying the alloy composition of the constituent material. Such systems, in the presence of an externally a pplied bias, can exhibit resonant tunneling behavior that is quite dif ferent from previously studied multi-barrier materials, because of the unique coupling of the quasi-bound states between the graded quantum wells. In this paper, we explicitly compute the electron transmission coefficient T(E) for such systems as a function of the multi-barrier g eometry and internal slopes of the quantum wells to obtain novel trans mission coefficient spectra and discuss their implications.