What is the significance of Fermi Temperature?

[Old Guy]

Homework Statement

What is the significance of Fermi Temperature?

Homework Equations

I know it is the ratio of the Fermi energy (or the chemical potential at the Fermi energy) to the Boltzmann constant.

The Attempt at a Solution

What does it MEAN? I've worked out the Fermi temperature for copper for example, and what I visualize is that if you start at absolute zero, and add thermal energy, you really only change the energy of the conduction electrons; the "bound" or "non-valence" electrons are unaffected because they are all at lower energy levels. I interpret this as perhaps an increase in the kinetic energy of the conduction electrons, but they still remain with the atoms and the underlying orbitals/energy levels maintain essentially the same structure, which is why the chemical potential remains basically unchanged below the Fermi temperature.

However, conductivity is inversely proportional to temperature, which I've seen attributed to increased vibrational energy of the lattice interfering with the movement of the conduction electrons as the temperature increases. But this would imply to me that the additional thermal energy is going to the bound electrons.

I'd like to understand what's really happening here. Also, I'd like to know why it is interpreted as a temperature (I know the units work out, other than that . . .)

Thanks.

 

[Greg Bernhardt]

The Fermi temperature is the temperature above which a material can no longer be considered a metal. The Fermi temperature is named after Enrico Fermi, who made important contributions to quantum statistics, statistical mechanics, and statistical thermodynamics.