Semimetal
A semimetal is a metal where the fermi energy is in the band but the electron density is pretty
low. The right plot in fig. 47 is a bit more a metal than a semimetal. So in a semimetal there are just
Figure 47: Two kinds of a semimetal.a few states in the upper band. This can happen if there is something that’s almost a semiconductor
but in one direction in k-space the bands overlap in energy. That means that a semimetal is a metal
but with a low electron density. A classical example of a semimetal is bismuth.