Electron transport in AlGaInP quantum well lasers

By placing a direct-gap monitor layer (or collector) in the p-cladding layer of red-emitting AlGaInP laser diode structures, we have studied the transport of electrons through this layer by observation of spontaneous emission. Pulsed optical excitation superimposed on cw electrical injection has been used to determine the delay time between optical injection of carriers into the well and radiative recombination from the monitor pit. Computer simulations using measured values of minority carrier lifetime for the well and monitor layer show that the transit time for electrons through the p-cladding layer correspond to an electron mobility of 160 cm(2)/V s. (C) 1999 American Institute of Physics. [S0003-6951(99)02238-X].