Study On The Technology Of Ring Cavity Regenerative Amplification For Ho:YAG Crystal

2 μm lasers have been considered as the light of the future for their application involving almost every fields. With the development of mode locking, 2 μm ultrashort laser pulses have wider applications in fields of medicine, military, research. But considering the limited single pulse energy of the mode-locked pulses for only about n J magnitude, these applications have been circumscribed.With the invention and development of the regenerative amplification, we can amplify the pulse energy of the mode-locked pulses to obtain laser pulses with the energy up to m J magnitude, breaking the limits of single pulse energy of the ultrashort laser pulses. Mode-locked laser pulses after regenerative amplified can maintain the cherished characteristics of the mode-locked pulses, galvanizing a deeper application of ultrashort laser pulses in many fields, such as strong-field physics, multiphoton ionization.First, this paper makes a detailed investigation of the regenerative amplification and its seed mode-locked laser at home and abroad in the last few years, and does systematic analysis and solvation of the theory of the regenerative amplification. From the rate equation of the laser pulses to the amplification of the rectangular wave, then to the amplification of the ultrashort laser pulses, and finally to the theoretically model of the regenerative amplification, the feasibility and the strengths of the regenerative amplification can be proved theoretically.In addition, this paper shows the preparation of the experiment of the regenerative amplification. First, advantages and disadvantages of active and passive mode-locking lasers are analyzed, and then from the pulse width, rate frequency, etc, this paper introduces the main parameters of the mode-locked laser, and does laser beam transform to match of light patterns of the regenerative amplifier. Second, a brief introduction of the isolation system, the usage of the Pockels Cells, and the way of choosing single pulse. Third, a regenerative resonator cavity is designed, giving the resonant cavity parameters such as laser pattern change and its range of stability, and introducing pump sources the ring cavity.Finally, for regenerative experimental part, the workings of the seed pulse in the regenerative resonant cavity are illustrated, from the output power, single pulse energy, pulse width and other parameters, the regenerative experimental data are analyzed and the causes of these phenomena are explained. At the rate frequency of 1 k Hz, the maximum pulse energy of 144 μJ is obtained. At the rate frequency of 5 k Hz, the maximum pulse energy of 62.2 μJ is obtained, with the pulse duration of 1.6 ns. And with the measurements of the laser output in the mode of cavity dumping, a comparison between the mode of cavity dumping and the mode of regenerative amplification is made.