Submillimeter and millimeter optical constants of liquid nitrogen

We present power absorption coefficient measurements of liquid nitrogen in the range 4–28 cm−1 and measurements of the average value of the refractive index for the range 4–10 cm−1. The measurements were performed with a polarizing Michelson interferometer. The power absorption coefficient rises quadratically from 0.006±0.002 nepers cm−1 at 4 cm−1 to 0.381±0.009 nepers cm−1 at 28 cm−1. The average value of the refractive index is 1.20±0.03 between 4 and 10 cm−1.