Abstract

Optoelectronic bistability was observed in gallium phosphide light emitting diode. Three device functions—current, optical output intensity, and optical output peak wavelength—showed bistable characteristics. The bistability is based on negative differential resistance occurring in the forward biased current–voltage characteristics. The switching voltage was ~15 V. Based on these I–V characteristics, the two stable states are (1) high impedance state in which the current is ~1 mA and the optical output has a weak-intensity yellow light with peak wavelength at 569 nm, and (2) low impedance state in which the current is ~200 mA (depending on the load resistance) and a strong-intensity (an order of magnitude stronger) green light with peak wavelength at 543 nm. We show the output–input intensity hysteresis curve obtained with an optical filter and typical optical output spectra of the bistable states of a GaP light emitting diode. The spectra show the intensity and peak wavelength differences between the two states.

© 1988 Optical Society of America