The diode is working as a cooler. 2012/2/28 Harry Veeder <hveeder...@gmail.com>
> According to the second law you can only get a system to do "work" if > parts of the system are at different temperatures. In this situation > the system is a diode and it does work by converting heat into light. > It is hard to tell from the description, but I am guessing the entire > diode is at an elevated temperature. > > harry > > On Tue, Feb 28, 2012 at 12:20 PM, Daniel Rocha <danieldi...@gmail.com> > wrote: > > Why do you think it would violate the 2nd law? I don't understand. > > > > 2012/2/28 Harry Veeder <hveeder...@gmail.com> > >> > >> On Tue, Feb 28, 2012 at 11:57 AM, Daniel Rocha <danieldi...@gmail.com> > >> wrote: > >> > Pay attention at this: > >> > > >> > " Experiments directly confirm for the first time that this behavior > >> > continues beyond the conventional limit of unity electrical-to-optical > >> > power > >> > conversion efficiency." > >> > > >> > It is above the conventional, not that it produces energy out of > >> > nothing. > >> > This is just a way of saying that it exceeded expectation of light > >> > emission > >> > for a LED. > >> > >> > >> Yes. It uses electricity to change heat into light. The abstract: > >> > >> "A heated semiconductor light-emitting diode at low forward bias > >> voltage V<kBT/q is shown to use electrical work to pump heat from the > >> lattice to the photon field. Here the rates of both radiative and > >> nonradiative recombination have contributions at linear order in V. As > >> a result the device’s wall-plug (i.e., power conversion) efficiency is > >> inversely proportional to its output power and diverges as V > >> approaches zero. Experiments directly confirm for the first time that > >> this behavior continues beyond the conventional limit of unity > >> electrical-to-optical power conversion efficiency." > >> > >> > >> however, wouldn't this require a violation of the second law of > >> thermodynamics? > >> > >> Harry > >> > > > > > > > > -- > > Daniel Rocha - RJ > > danieldi...@gmail.com > > > > -- Daniel Rocha - RJ danieldi...@gmail.com
