NONLINEAR SPATIOTEMPORAL DYNAMICS IN P-N-JUNCTIONS INCORPORATING QUANTUM-WELLS - LONGITUDINAL TRANSPORT

A novel light emitting device is proposed and demonstrated experimenta lly. The device consists of a GaAs quantum well placed on the n-side o f the depletion region of a Ga1-xAlxAs p-n junction. Electric fields a re applied parallel to the layers between two point contacts. The oper ation of the device is based upon the accumulation, in the quantum wel l, of excess hot electrons injected from the n region of the barrier v ia tunnelling and thermionic emission. Negative charge accumulation in the depletion region changes the potential profile, and therefore lea ds to a decrease in the depletion width and the potential barrier in t he p-side of the junction. Hot holes then diffuse into the quantum wel l to recombine with the electrons. Emitted light intensity is independ ent of the polarity of the applied voltage. Theoretical modelling of t he device is carried out by solving Schrodinger's and Poisson's equati ons self-consistently by incorporating tunnelling, and diffusion dynam ics of the hot carriers.