Lasing Without Inversion in Mercury at 253.7 nm

Satus and Outlook

The three lasers at 435.6 nm, 546.1 nm and 404.7 nm are developed and provide more than the required power of 150 mW at 435.6 nm and 0.3 mW at 546.1 nm.

In a next step, the linewidth of the two driving lasers will be measured since it constitutes a key factor for LWI. Subsequently, the lasers will be brought together in a mercury gas cell to confirm the theoretical predictions in [1] with a 253.7 nm laser system which depends on fourth-harmonic generation. Afterwards, the mercury gas cell will be set into a resonator to demonstrate LWI at 253.7 nm for the first time.

Mercury also provides a 4-level scheme which allows LWI in the VUV regime at 185 nm. For this scheme the required driving laser wavelengths are 434.8 nm and 302.8 nm which are technically accessible.

Alternative 4-level scheme in Hg

References