Optical constants of far infrared materials. 2: crystalline solids.
The far infrared optical constants of four crystalline materials at room temperature and at 1.5 K are reported. The materials are crystal quartz, sapphire, germanium, and silicon. The first two of these are birefringent (uniaxial) and both sets the range from 30 cm(-1) to 350 cm(-1).
Loewenstein
E V
EV
Smith
D R
DR
Morgan
R L
RL