On the “atomic/electronic” level, what is actually happening that causes the transport of heat from one side to another via the Peltier effect(?)

Question

I get the principle of the Peltier effect. But what is *actually* happening on the atomic level when currect goes through a N- and P-doped semiconductor. Sure, this causes one side to heat up by releasing heat, and the other to cool down by absorbing heat. But why do the materials behave that way? How does the filling of electrons (when they re-combine with the “holes”) cause a heating on one side, but cooling on the other and not necessarily vice-versa?

In: Chemistry

Answer 1

It is due to the conversion of that voltage and current into power, which dissipates as heat. Power is equal to the product of voltage and current. Those charge carriers bring with them the stored energy necessary to produce heat when they flow, and as you remember cold is merely the absence of heat. No charge carriers on one side means no potential for power to dissipates as heat. Or a lower potential anyway.