Question about maximum energy efficiency

Originally posted by humy
I may have become disappointed in not quite finding the answers I was seeking for the theoretical maximum energy efficiencies for electric lamps and solar cells, by I have just found this video about spintronics ( sending signals down wires not via electric current but by changing the spin of the electrons ) research that give extremely good clues of what, in v order of magnitude of difference? Would anyone in the scientific community have a clue on this?

I had assumed that plasmotics and spintronics would probably not meaningfully combine but I have just found about “spinplasmonics” which DOES combine the two:

http://en.wikipedia.org/wiki/Spinplasmonics
“...Spinplasmonics is a field of nanotechnology combining spintronics and plasmonics. The field was pioneered by Professor Abdulhakem Elezzabi at the University of Alberta in Canada. In a simple spinplasmonic device, light waves couple to electron spin states in a metallic structure. The most elementary, which is very easy, spinplasmonic device consists of a bilayer structure made from magnetic and nonmagnetic metals. It is the nanometer scale interface between such metals that gives rise to an electron spin phenomenon. The plasmonic current is generated by optical excitation and its properties are manipulated by applying a weak magnetic field. Electrons with a specific spin state can cross the interfacial barrier, but those with a different spin state are impeded. Essentially, switching operations are performed with the electrons spin and then sent out as a light signal.
Spinplasmonic devices potentially have the advantages of high speed, miniaturization, low power consumption, and multifunctionality. On a lengthscale that is less than a single magnetic domain size, the interaction between atomic spins realigns the magnetic moments. Unlike semiconductor-based devices, smaller spinplasmonics devices are expected to be more efficient in transporting the spin-polarized electron current...
...”

don't know what effect this could have on the maximum energy efficiency for a computer.