Light-emitting transistor
A light-emitting transistor or LET is a form of transistor that emits light. Higher efficiency than light-emitting diode is possible.History
Reported in the January 5, 2004 issue of the journal Applied Physics Letters, Milton Feng and Nick Holonyak, the inventor of the first practical light-emitting diode and the first semiconductor laser to operate in the visible spectrum, made the world's first light-emitting transistor. This hybrid device, fabricated by Feng's graduate student Walid Hafez, had one electrical input and two outputs and operated at a frequency of 1 MHz. The device was made of indium gallium phosphide, indium gallium arsenide, and gallium arsenide, and emitted infrared photons from the base layer.