Investigation On All-solid-state CW Single-frequency Tunable Ti: Sapphire Laser And Intracavity Frequency-doubled Ti: Sapphire Laser

All-solid-state continuous-wave(CW)single frequency Ti:sapphire laser with continuous frequency-tuning is the best tunable solid-state laser by now.It can efficiently generate 700?1000nm laser.Ti:sapphire laser with good tunable ability,high output power and good intensity noise characteristics is widely used in quantum optics,laser spectroscopy,atomic physics,biomedical and many other research.The nonlinear frequency conversion technology make the Ti:sapphire laser products more particular wavelength laser with high quality that is difficult for many other types of lasers.With the rapid development of nonlinear crystallography,it appeared many excellent nonlinear crystals such as LBO,BIBO,PPKTP,et al.,which are used as good frequency doublers in intracavity frequency-doubled Ti:sapphire laser to produce blue to near-ultraviolet laser and expand the application field of Ti:sapphire laser.In this paper,the all-solid-state CW tunable Ti:sapphire laser is first built and its frequency-tuning characteristic is investigated.Then,by introducing a nonlinear loss to the resonant,a tunable Ti:sapphire laser without intracavity locked etalon is achieved.Lastly,a single-frequency 397.5nm laser by means of an intracavity frequency-doubled Ti:sapphire laser is presented.The main works are as fellowing:1.An optical diode which can be used in CW tunable Ti:sapphire is designed by analyzing the optical activity of quartz and magneto-optic crystal.According to the tuning characteristic of birefrigent filter and etalon,a three-plate birefrigent filter with the thickness of 0.5:2:8mm is designed as a rough frequency-tuning element and a etalon with the thickness of 0.5mm is chosen as a fine frequency-tuning element.A CW single-frequency tunable Ti:sapphire laser with compact configuration is presented,in which a three-plate birefringent and an etalon is inserted into the resonator as the frequency-tuning components.The oscillating wavelength of the Ti:sapphire laser can be tuned from 760nm to 825nm when the transmission peak of the intracavity etalon is locked on the oscillating frequency of the laser and the continuous frequency-tuning range of the Ti:sapphire laser reaches to 15GHz.The obtained Ti:sapphire laser is successfully applied to scan the saturation absorption spectroscope of D1 transition of 87Rb atoms around the wavelength of 794.97nm.2.On the basis of the research that the intracavity nonlinear loss have an effect on the tuning characteristic of the Ti:sapphire laser,A CW single-frequency Ti:sapphire laser with continuous frequency-tuning and low intensity noise is presented,in which an extra nonlinear loss crystal(BIBO)is placed inside the ring resonator composed of six mirrors instead of the traditional etalon locking system.The Ti:sapphire laser can produce a tunable stable single-frequency laser with low intensity noise at the same time and the continuous frequency-tuning range is as large as 48GHz.3.The optimal length of the gain medium in intracavity frequency-doubled and single-frequency Ti:sapphire laser is given by analyzing threshold equation of the Ti:sapphire laser.In that case,a CW single-fr~equency intracavity frequency-doubled Ti:sapphire laser with low threshold pump power and high output power is presented by using LBO/BIBO as a frequency doubling crystal and a single-frequency 397.5nm laser is obtained.The output power of the intracavity frequency-doubled Ti:sapphire reaches 780mW and 1.58W,respectively,when using LBO and BIBO as frequency doubling crystal.Innovative works in this article:(1).Joining the bias circuit into the locking system to make sure the transmission peak of the etalon is locked on the oscillating frequency of the laser.A CW single-frequency tunable Ti:sapphire laser is achieved with the method of locking the intracavity etalon.(2).A CW single-frequency Ti:sapphire laser with continuous frequency-tuning,low intensity noise and large frequency-tuning range is achieved by inserting an extra nonlinear loss crystal in the resonant.It's a new method to obtain the CW single-frequency Ti:sapphire laser with continuous frequency-tuning which needs no intracavity etalon locking system.(3).A method of choosing optimal length of the gain medium of the CW single-frequency intracavity frequency-doubled Ti:sapphire laser is given and a CW single-frequency intracavity frequency-doubled Ti:sapphire laser with low threshold pump power and high output power is achieved.