Time-resolved carrier recombination dynamics of 1.3-1.8 mu m broadband light emitting diode structures

We present a time-resolved study of carrier recombination dynamics of broadband Light emitting diode structures comprised of a series of InGaAs/lnGaAlAs digital pseudoalloy short period superlattices fabricated by molecular beam epitaxy. The structure consists of three quantum wells equally spaced in emission energy over the 1.3-1.8 mu m range. We performed a time-resolved study of carrier recombination process for each quantum well using optical pumping. Experimental results show that carrier tunneling across adjacent wells plays a major role in the overall carrier population distribution across the three wells. By tailoring the thicknesses of barriers and wells of the structure, uniform spectral emission covering 1.3-1.8 mu m range can be achieved. (C) 1996 American Institute of Physics.