Research On All-solid-state Pulsed Laser Based On Novel Magnetic Nanomaterial Saturable Absorber

In recent years,mode-locked lasers have been widely used in the fields of optical fiber communication,laser medical treatment,remote sensing,optical signal processing,military and so on.Passive mode-locked technology based on saturable absorber has become the mainstream of mode-locked laser.So far,many types of saturable absorbers have been successfully applied,such as semiconductor saturable absorption mirrors,carbon nanotubes,graphene,topological insulators,transition metal sulfides,etc.However,these saturable absorbers still have some limitations,which limit the development of lasers to a certain extent.Therefore,it is still of great practical value to explore new saturable absorbers and study mode-locked lasers based on new saturable absorbers.With the rapid development of nanotechnology,the excellent physical properties of magnetic nanomaterials have attracted extensive attention.Previously,magnetic nanoparticle materials as saturable absorption materials used in lasers have been affirmed by many researchers.Recently,researchers have found that this kind of material can also be made into magnetic nano sheet materials.In a sense,magnetic nano sheet materials have the properties of two-dimensional materials,which makes this kind of materials have a fundamental transformation relative to nanoparticles.In this paper,1342nm passively Q-switched mode-locked operation in all solid state Nd:YVO₄ laser is realized by using this new saturable absorber magnetic nanosheet material.The following is the main content of this paper:1.We have prepared new magnetic nanosheets and studied their properties,focusing on the saturation absorption characteristics of new magnetic nanosheets.2.The principle of Q-switched mode-locking of magnetic nanosheets saturable absorber is studied theoretically,and the pulse laser based on the new saturable absorber is designed.3.A novel pulsed laser based on magnetic nanosheets saturable absorber is experimentally studied,and the Q-switched mode-locked operation of 1342nm all solid state laser is realized.The Q-switched mode-locked laser based on magnetic nanoparticle material and magnetic nanosheets material is compared.The pulse width of 921ps is achieved by using nanoparticle absorber,and 558ps is achieved by using nanosheets absorber.