Higher Physics. Semiconductor Diodes. Light Emitting Diode 1. An LED is a forward biased diode When a current flows, electron-hole pairs combine at the p-n junction.
whereh – Planck’s Constant
f – light frequency
Find the recombination energy for the following LEDs –
a) red – λ = 650 nm
b) blue – f = 4.5 x 1014 Hz
p-n junction where electron-hole pairs are generated by absorbed photons from incident light