Ultrastable carbon dioxide (CO2) lasers

This paper reviews the spectral purity, frequency stability and long-term stabilization of CO2, isotope lasers developed at MIT Lincoln Laboratory. Extremely high spectral purity and short-term stability of less than 1.5 x 10-13 have been achieved and will be discussed. A long-term stabilization technique, which was used to line-center lock any regular or hot-band CO, isotope laser transition, is described. A brief description on using CO, lasers as secondary frequency standards is also given.