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Ultra-efficient LED puts out more power than is pumped in (wired.co.uk)
14 points by amitt 4683 days ago
2 comments

The headline is inaccurate. The LED outputs more power than the electrical power input. The remainder of the energy comes in the form of heat from the surrounding environment. It works by applying slightly less voltage than the LED's bandgap and then relying on electron-phonon coupling to kick an electron to an orbital above the band gap.

That kills off a quanta of energy from whatever phonon mode gave the kick (which cools the LED), and the electron emits a photon when it relaxes back into the valence band. The LED is no longer in thermodynamic equilibrium with the surrounding environment, so heat flows into the LED.

Considering the expense we go to in order to cool things down, could this be scaled up to provide us with a light source and a cheaper way to cool things?

Right now, most energy that becomes heat is considered wasted because of limited applications in turning that heat back into usable energy.

That's what I'm thinking too. The first thing I thought of when reading about it was refrigerator/air-conditioner
Thanks for clearing this up. For the innocent bystander the headline sounded like something coming out of a Troll science strip. I was only missing the "magnets"...
Shine the emitted light into space, global warming solved!

When did they say these things would be industrial scale again?

the powers that be curate certain titles that sound incorrect, but not the ones that ARE incorrect..