Bias-induced color-tuned semiconductor devices

A three terminal light emitter in which the emission wavelength is selected by an applied voltage and the emission intensity is independently modulated by an applied current has been demonstrated. The device exhibits coaxial optical output, a large wavelength separation (8210 /spl Aring/ or 7640 /spl Aring/, /spl Delta//spl lambda/=570 /spl Aring/), low operational voltages (<5 V) and currents, and high emission contrast ratios (as large as 159:1 and as small as 1:76). Having selected the wavelength the optical output power can be independently modulated without loss of wavelength selectivity. Wavelength switching can be accomplished while maintaining a high contrast ratio and optical output power.