Changing an LED’s color by changing its temperature – it’s quantum mechanics! @SeamusBlackley

Quantum Mechanics! (The resonant frequency of the semiconductor in this LED is temperature dependent) pic.twitter.com/wXCTSYVLm8

— Seamus Blackley (@SeamusBlackley) May 28, 2021

An awesome tweet by Seamus Blackley demonstrating heating an LED then rapid cooling in liquid nitrogen. Changing the temperature of the LED changes the resonant frequency of the LED semiconductor, as it is is temperature dependent due to Quantum Mechanics!

Think of the spacing of the atoms in the LED like the frets on a guitar. When we change the temperature, the neck expands and contracts, which makes the difference between notes get bigger or smaller. This difference determines the color of the LED, so it changes!

You can read the thread on Twitter here.