All-solid-state Single-frequency Ti:Sapphire Laser With The Board Tunability In 900nm Wave Band

With the rapid development of the all-solid-state single frequency laser with the board tunability and the in-depth study of light interacting with atomic,the single frequency lasers with the board tunability in 900 nm wave band are corresponding to a few cesium atomic absorption lines and have important application prospects in optical atomic clocks,cold atom physics,light-atomic manipulation,quantum information storage,and other areas of the research in recent years.And the single frequency blue lasers with the board tunability after the frequency doubling also correspond to a few transition absorption lines such as the barium ion ground state,cesium atomic upper state and so on.The blue laser occupies the important leading role in a few scientific research projects such as the quantum calculation,the preparation of short wavelength entangled light field,the quantum manipulation and so on.These applications require lasers of 900nm band to have high output power,good beam quality,good frequency stability,narrow linewidth,low noise,good repeatability and strong anti-interference ability.In order to satisfy these performance indexes,we have completed the following work to design the Ti:sapphire laser in 900nm wave band for high output power,single-frequency and board tunability in this thesis:1.In this thesis,the physical characteristics,the absorption spectrum,the fluorescence spectrum,the polarization characteristic and the technique of narrowing linewidth of the Ti:sapphire crystal are introduced.For the purpose of the experiment,we design the experiment device what have the technique of narrowing linewidth at the same time the ability of Continuous wide tuning.2.From the four-level rate equations in theory,calculated the threshold pump power and output power varies with the pattern matching relation between pumping laser and oscillation laser.It provides a theoretical basis for the diminution of the threshold pump power,the improvement output power and beam quality in 900 nm band infrared laser.3.In experiment,an embedded ring resonator consisting of six mirrors has been designed.It has a compact structure,stable power and can be like a self-compensation.By changing the distance between two concave mirrors in the embedded structure can be adjusted flexibly the pattern matching relationship between pumping laser and oscillation laser to achieve the best optical to optical conversion efficiency.With the pump power of 15 W all-solid-state laser at 532nm,the average output power more than 2 W in the broad tunable wave range from 852 nm to 934 nm has been obtained.The long-term stability within three hours and the beam quality factor M2 are better than±0.7%and 1.04,respectively.4.The single frequency Ti:sapphire laser in 911 nm expanded research in experiment.A LBO crystal of 7.5 mm long is inserted the intracavity of Ti:sapphire laser for the second harmonic generation.With the pump power of 11.64 W all-solid-state laser at 532nm,output power of 1.63W single-frequency blue light in 455.5nm has been obtained.The green-blue light conversion efficiency is 14%;the long-term stability within three hours is better than±2.5%and the M~2 factors are M_x~2=1.31 and M_y~2=1.84respectively.