All-solid-state Cw Single-frequency Ti:Al₂O₃ Laser

Ti-sapphire(Ti³⁺:Al₂O₃) laser has many prominent advantages such as wide fluorescent-band(600～1200 nm) and wide absorption-band(400～600 nm),high conversion efficiency,and the facilitated functioning and so on.It is one of the solid-state lasers with most wide-band tuning range.The 780nm wavelength emitted from the Ti-doped sapphire laser just corresponds to the F_3/2-F_1/2 transition of rubidium atoms,so a Ti-sapphire(Ti³⁺:Al₂O₃) laser can be utilized to prepare ultra-cold atoms of rubidium.On the other side,780 nm can be down-converted to 1560 nm through a non-linear optical process in an optical parametric oscillator,in which a pair of entangled optical beams will be produced,and the entangled light at 1560nm wavelength propagates in fiber with low loss and low dispersion.It is compatible with the current fiber communication network.The generation of the entangled states of light at 1560nm provides necessary resources for developing quantum key distribution in optical fiber.In this paper,a continue-wave all-solid-state Ti³⁺:Al₂O₃ laser pumped by a diode-pumped intracavity frequency-doubling Nd:YVO₄ with single-frequency output at 780nm wavelength is reported.First of all,we designed and experimentally constructed a high-power single-transverse mode Nd:YVO₄/LBO green laser with the maximum output of 9W,which provided a reliable and stable pump source for the titanium-doped sapphire laser.In order to achieve the maximum absorption of pumping light and to reduce the useless residual absorption,we calculate the optimal doping concentration and the appropriate length of the Ti-sapphire crystal based on the analysis to its construction and features.Taking fully account of astigmatism compensation,we designed the ring resonator of the laser.Eventually,an output of 700m W at 780nm was achieved,with an intensity fluctuation less than 0.5%(20 minutes).The slope efficiency of the laser is 17.5%. This paper includes the following four parts:Chapter one:Introduction.In this part,the development of Ti:Al₂O₃ laser is briefly summarized.Chapter two:All-solid-state high power continue-wave TEM₀₀ mode Nd:YVO₄/LBO green laser.In this chapter,all-solid-state high power continue-wave TEM₀₀ mode Nd:YVO₄/LBO green laser is introduced.In the design of the laser, the optimal selection of the coupling system and the characters of Nd: YVO₄ and LBO crystals were considered,the configuration of the v-folded laser resonator with three mirrors was analyzed,the size and the location of waist were calculated.At last,the TEM₀₀ mode green laser of 9W was experimentally obtained under a pump power of 26.8W.Chapter three:Theoretical analyses and experiment research on continue-wave Ti:Al₂O₃ laser.In this chapter,we theoretically and experimentally analyze the all-solid-state continuous single-frequency Ti:sapphire laser.The chemical and spectrum-physical characteristics of Ti:sapphire crystal are introduced firstly.Using optical transmission matrix,the configuration of "8" ring resonator is analyzed and the parameters of cavity are selected.The threshold and the slope efficiency of the laser are calculated.Eventually,a cw single-frequency output of 700mW at 780nm laser was experimentally produced from the Ti:sapphire laser made by us.Chapter four:Conclusions and prospection.