Lasers utilizing $CO_2$ isotopes

The lasing spectra and energy characteristics were investigated for lasers operating with the isotopes $C^{12}O_2^{16}$, $C^{13}O_2^{16}$, $C^{12}O_2^{18}$, $C^{12}O^{16}O^{18}$. It was found that the output power of a laser utilizing the $CO_2$ isotopes was determined by the content of a particular isotope in the carbon dioxide gas. For equal enrichments, all the isotopes investigated, with the exception of $C^{12}O^{16}O^{18}$, gave comparable output powers. The unsaturated gains were identical for the most intense transitions of the symmetric molecules; the gain was a factor of two less for the asymmetric molecule. The gain rose linearly with increasing enrichment. The ultimate specific power output, given by the product of the saturation power density and the gain, was practically independent of the enrichment.