Re: [Phys-l] solid state physics

[John Denker <jsd@av8n.com>]

fizix29@aol.com wrote:
>  Why aren't there light and heavy electrons just as there are light and heavy holes?

Good question.

Simple answer:  there are.
  http://www.google.com/search?q=light-electrons+light-holes

In ordinary _silicon_, there are two branches of the hole dispersion
relation (light holes and heavy holes) but only one branch of the
electron dispersion relation ... because of details of the silicon
band structure.

If you cobble up a material with a different band structure, you
can get a different result.

For details see a book on solid-state physics e.g. Ashcroft & Mermin.
I tried googling but did not immediately find any cogent discussions
online.  I can find the diagram:
  http://www.uvm.edu/~dcloughe/images/si.gif
and others via
  http://images.google.com/images?q=silicon+band-structure
but not much useful discussion.