More on Spintronics

segment writes "'We have discovered the equivalent of a new 'Ohm's Law' for spintronics - the emerging science of manipulating the spin of electrons for useful purposes,' says Shoucheng Zhang, a physics professor at Stanford. 'Unlike the Ohm's Law for electronics, the new 'Ohm's Law' that we've discovered says that the spin of the electron can be transported without any loss of energy, or dissipation. Furthermore, this effect occurs at room temperature in materials already widely used in the semiconductor industry, such as gallium arsenide.'"

Comments

Re:Does Anyone Remember Cold Fusion?

[fugu13]

Sorry, no.

Entropy is not an absolute law, but a law based on extreme probabilities. In any reaction, certain quantities are completely conserved. One of these is energy.

The increase in entropy that occurs is due to energy being converted into less usable forms, such as from motion (kinetic energy) to heat (thermal energy).

It is not actually a decrease in total energy. Energy is perfectly conserved in any reaction.

In subatomic reactions, there is no place for energy to go, so to speak. In fact, the only thing energy really is is the motion (and mass, though those are remarkably interlinked) of subatomic particles.

When two subatomic particles collide, if neither of them splits or gives of any other particles, the energy remains entirely in the two particle system (that is, all that changes is kinetic energy; speed). Well, direction changes as well.

Mod parent down; he is incorrect. (or not, I'm actually in favor of the mod up only philosophy, but parent would be a good one to mod down if you believe in modding factually incorrect posts down).