(PhysOrg.com) -- For the first time, researchers have demonstrated that an LED can emit more optical power than the electrical power it consumes. Although scientifically intriguing, the results won’t immediately result in ultra-efficient commercial LEDs since the demonstration works only for LEDs with very low input power that produce very small amounts of light.
Note how the efficiency sharply drops with a lower temperature; this looks a lot like a heat pump, that we know to not violate the second law.
Based on that my guess is that the loss of local entropy causes a raise of the entropy elsewhere. Probably whatever you’re using to keep the LED warm.