Self-injection locked CW single-frequency tunable Ti:sapphire laser

Abstract

A self-injection locked continuous-wave (CW) single-frequency tunable Ti:sapphire laser is demonstrated in this paper. Unidirectional operation of the presented Ti:sapphire laser is achieved by using a retro-reflecting device which can retro-reflect a seed laser beam from one direction back into the counter-propagating field. On the basis, the influence of the transmission of output coupler on the unidirectional operation is investigated and it is found that stable unidirectional and single-frequency operation of the Ti:sapphire laser is achieved when the loss difference between both output directions is larger than a certain value, which is easy to be realized by choosing the transmission of output coupler. When the output coupler with transmission of 6.5% is utilized, the maximal 5 W CW single-frequency Ti:sapphire laser with stable unidirectional operation is obtained with the pump power of 18 W. The measured power stability and M are better than ±0.9% and 1.1, respectively. The maximal tuning range and continuous frequency-tuning ability are 120 nm and 40.75 GHz, respectively.

A Review of Progress about Birefringent Filter Design and Application in Ti:sapphire Laser

“…One primary reason is that the tuning range of the lasers is restricted by the limited film coating for a long time. Another reason is that for the frequently-used gain medium of the tunable laser, whose fluorescence emission spectrum is relatively narrow [57], researchers are still in the habit of using the on-axis BRF in practical application [58]. In 2007, Ding et al realized a tunable dual-wavelength output in Ti:sapphire laser with one wavelength range from 700 nm to 756.5 nm, and another from 830 nm to 900 nm by employing a 0.5 mm BRF with the optic axis on its surface [59].…”

10 W injection-locked single-frequency continuous-wave titanium:sapphire laser

“…There has been growing demand for higher power lasers with narrow linewidth in the field of cold atom experiments like atom interferometers using multi-photon process [5], which needs a high power laser as possible with a spectral purity and a wavelength tunability to atomic resonance. Although the wavelength range of Ti:sapphire lasers covers many of the resonant wavelength of Alkali atoms, the output power of single-frequency injection locked Ti:sapphire lasers remained 5-6.5 W, even when 20 W class pump lasers were used [11,12]. Therefore, other 10 W-class lasers with a less tunable wavelength range have been chosen for above applications [13][14][15].…”

“…Here, we demonstrate a higher-power CW injection locked Ti:sapphire laser than ever reported. Since the Ti:sapphire cavity did not contain an isolator or a birefringent filter, which were included in the previous lasers [11,12], the round-trip loss decreased to 2%. By optimizing an output coupler and beam waist diameter of a pump beam for such configuration, slope efficiency was increased to 51% at a wavelength of 780 nm.…”

Half-Watt Tm3+-Doped Fluoride Fiber Laser at 785 nm

“…Higher output power can be achieved with semiconductor laser amplifiers and laser beam combing techniques [5], but the beam quality is always degraded and power scaling is usually limited by thermal issues of in the semiconductor. this wavelength band [6], further power scaling is limited by thermal-optical problems and the crystallographic properties of Ti:sapphire. In addition, Ti:sapphire lasers require careful alignment and frequent maintenance.…”