Optoelectronic devices

Review—On The Search for Efficient Solid State Light Emitters: Past, Present, Future

“…Therefore, surprisingly, one can have an efficiency of fluorescence above 100% by transforming some heat into photons, the luminescence of materials playing the role of a heat engine, like the compressor in a refrigerator. 173 The path to 100%+ LEDs.-The same question of physical limits exists, of course, for LEDs with their direct conversion of electricity into light. We saw in 2.1 that the WPE is equal to η EQE x hν/qV bias .…”