Efficient, single frequency LiF:F 2 − laser

Tunable, single mode, solid state lasers are required for many spectroscopic and remote sensing applications in the near infrared region. Although the important wavelength range between 1.05 and 1.3 µm is only covered by colour centre lasers, widespread use of LiF:F 2 − lasers has been limited by relatively low crystal quality, passive loss and F 2 − photodegradation processes. Narrowband LiF:F 2 − lasers have, consequently received little attention [1], operaring with low efficiency and poor long term stability. However, the recent development of crystals containing more stable F 2 − centres as well as improved crystal irradiation and annealing techniques have led to increased operating lifetime and laser efficiency [2]. (We have observed no degradation in laser performance during seven months of operation). Here we demonstrate efficient single frequency operation using a recently-developed LiF:F 2 − rod in an innovative dual cavity configuration. We anticipate that this resonator will be widely applicable to other laser media.