## [Electrons and Holes in Semiconductors](https://www.chu.berkeley.edu/wp-content/uploads/2020/01/Chenming-Hu_ch1-3.pdf)



## [Optical Properties of Solids](http://web.mit.edu/6.732/www/opt.pdf) M. S. Dresselhaus


## https://en.wikipedia.org/wiki/Semimetal