In reply to David Roberson's message of Fri, 25 Sep 2015 15:40:33 -0400: Hi Dave, [snip] >This discussion is interesting. Perhaps the existing thermodynamic laws apply >mainly to black body types of interactions when radiation is associated. >Clearly the light emitted by an LED is not of that nature. It is narrow band >radiation at a level that is much higher in these bands than would be expected >according to the temperature of the device. > >Also, the DC input power contributes a significant portion of the net >radiation output in a direct conversion process. This behavior is very unlike >most of the systems used to derive the thermodynamic laws. Perhaps there >really does exist at least this one loophole that can be breached. > >A clear understanding of exactly how the random thermal motion within the LED >can be converted into light at this level of efficiency would be desirable. >Could it be that the random peaks in thermal energy that follow a Gaussian >distribution are the key? Near the thermal peak one might find that a little >help from the DC source is sufficient to cause electrons to jump into higher >orbitals. If enough of these occur in a short period of time a population >inversion may come into existance which would then drain the excess energy by >positive feedback and subsequent radiation pulses. The excess energy would >have to come from that random thermal motion that was tapped leading to >cooling of the device. > >Is this an example of an atomic Maxwell's demon?
It sounds a little like what I have tried to describe previously with evaporation. When water evaporates, only the fastest molecules make the grade, which essentially comprises a Maxwell demon. This process converts the kinetic energy of the fast molecules into potential energy, and leaves the slow molecules behind in the liquid, which is then cooler as a consequence. (We call a common example "wind chill".) By jumping to a higher orbital, in your description here above, kinetic energy is also converted into potential energy. I have in the past also suggested a setup where a plastic with an attached charged ligand that was free to rotate, was placed in a resonant chamber with a magnetic field which would convert microwaves into DC, thus preventing a two way flow of energy. That also constitutes a form of Maxwell demon, as the chamber would appear as a cold sink to the material. The chamber is tuned to resonate at the same frequency as the rotation frequency of the ligand. The general purpose of this setup is to convert random motion into ordered motion (thermal energy into DC). Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
