Font Size: a A A

Research Of Vanadate Crystal Laser Characteristics

Posted on:2013-10-20Degree:MasterType:Thesis
Country:ChinaCandidate:H B QinFull Text:PDF
GTID:2248330371469553Subject:Optics
Abstract/Summary:PDF Full Text Request
LD pumped solid-state pulse lasers with high peak power, short pulse width andhigh beam quality, which have many merits such as small size, light weight, firmstructure, long life duration, high stability and high conversion efficiency, have beenwidely used in the scope of military, industry, medical treatment and scientificresearches. As one of the main objectives of current research and developmentactivities within the laser community, LD pumped solid-state pulse lasers is constantlyimproving and fast developing, such as the constant improvement of output power,spatial beam quality, pulses stability and the decrease of pulse width. The foundationof those developments is selection of gain medium and laser modulator with perfectperformance. In this paper, we experimentally investigate the output performance ofcontinuous wave and passively Q-switched composite YVO4/Nd:Y0.9La0.1VO4lasersby Cr4+:YAG saturable absorbers in laser cavity as Q-switcher. With SWNTs,Graphene and SiC as saturable absorbers, the Q-switching, mode-locking and Q-switchmode-locking pulse laser performance of Nd:YVO4were also studied. The contentscan be outlined as follows:1. Review of the history and development of all solid state lasers, and the mainapproaches and new improvements of Q-switching and mode-locking pulse lasersnowadays are summarized. The optical properties of several Nd-doped mixed vanadatecrystals are simply introduced and compared with each other.2. A diode end-pumped continuous wave YVO4/Nd:Y0.9La0.1VO4crystal laserwas first demonstrated at 1064 nm with a compact plano-concave cavity.Themaximum output power was 11.9 W. With planar-planar resonator cavity, the focallength of thermal lens in the composite mixed crystal and the optimum reflectivity ofthe output mirror were also determined for the first time. With a Cr4+: YAG crystaloperated at an initial transmission (T0) of 60% passively Q-switchedYVO4/Nd:Y0.9La0.1VO4crystal laser was first demonstrated. The measured pulseduration of 8.8 ns, the pulse energy of 41.6μJ and the peak power of 4.63 kW are respectively obtained.3. We demonstrated the pulse characteristics of diode pumped Nd:YVO4crystallaser by using a transmission-type single-walled carbon nanotube as saturable absorber.With a compact V-type-cavity, steady Q-switching pulses were obtained. The measuredpulse duration was 332 ns at the repetition rate of 165.6 kHz. With a Z-type-cavity, 293mW was achieved at a repetition rate of 97.4 MHz. The peak power was 3 nJ at therepetition rate of 97.4 MHz, corresponding to the optical-optical efficiency of 19.9%.The stability of the mode-locking pulses was also studied in the experiment4. By using graphene as saturable absorber the pulse characteristics of Nd:YVO4crystal was demonstrated. With a compact V-type-cavity, steady Q-switching pulseswere obtained. The measured pulse duration was 262 ns at the repetition rate of 200kHz. With a Z-type-cavity, 127 mW was achieved at a repetition rate of 98 MHz.5. For the first time,we demonstrated Q-switching Nd:YVO4with SiC asmodulator. By using composite YVO4/Nd:YVO4and high power pump, 767 mwQ-switched mode-locking with a 90% modulation depth was obtained.
Keywords/Search Tags:All-solid-state laser, YVO4/Nd, Y0.9La0.1VO4, SWCNTs, graphene, SiC
PDF Full Text Request
Related items