摘要
为研究808nm和879nm两种泵浦光对Nd∶GdVO4晶体激光输出特性的影响,并比较两种不同波长泵浦所得连续输出光的效率高低,分析了Nd∶GdVO4晶体的能级结构和两种泵浦光作用下的激光输出特性,发现在879nm也有较强的吸收峰.用808nm和879nm两种不同波长泵浦Nd∶GdVO4晶体的过程是不同的,808nm泵浦是一种间接方式能量转移的过程,在此过程中有明显的热负载产生.而879nm泵浦是将粒子直接激励到激光辐射上能级,降低无辐射弛豫过程产生的热量.从理论上可知,879nm的泵浦量子效率要高于808nm的泵浦量子效率,对减少晶体的热产生有很强的优势.实验中采用激光二极管端面泵浦Nd∶GdVO4晶体直腔方案,研究了两种不同泵浦光泵浦Nd∶GdVO4晶体以获得1063nm的连续光,得到了两种光抽运时的斜效率,发现在同样实验条件下,879nm泵浦的输出光斜效率在小功率泵浦时略高于808nm;而在大功率泵浦的情况下明显高于808nm,最高达到38%.同时,在808nm抽运时,实验上获得了1341nm波长的激光,为光通讯的应用提供了一种光源.
In order to study the output characteristic of Nd∶GdVO4 influenced by 808 nm and 879 nm,coupled by comparison of the CW output laser efficency pumped by the two different wavelengths,the structure of the energy levels of the Nd∶GdVO4 crystal is investigated,and it is found that another absorption wavelength of 879nm is realatively strong.The output characteristics under 808 nm LD pumping and under 879 nm LD pumped are analyzed by experiments.The processes of pumping Nd∶GdVO4 crystal by laser beams of 808 nm and 879 nm wavelength are different.The pumping by 808 nm LD is a process of transfering energy by an indirect way.During the process,the obvious hot load will occur.But pumping by 879 nm LD will drive Nd3＋ ions into the laser emitting level,to avoid useless heat generation during no-radiation transition and reduce the thermal effects efficiently.Theoretically,the quantum efficiency of 879 nm is greater than that of 808 nm,so the heat produced from the crystal with pumping should be small.The way of pumping Nd∶GdVO4 crystal is used by laser diode from straight line cavity experimental program,and the process of producing 1 063 nm CW by pumping Nd∶GdVO4 crystal is studied using two different pumping wavelengthes.Lasers under these two different pumping wavelengths are obtained.With the same experimental conditions,the output slope efficiency of pumping crystal by 879 nm LD is a bit higher than by 808 nm in low power.But the output slope efficiency of 879nm is greater than that of 808 nm in high power,and the maximum reaches 38%.Meanwhile,a laser of 1 341 nm is achieved when the pumping at 808 nm,which could be a kind of light source for optical communication.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2010年第10期1747-1751,共5页
Acta Photonica Sinica
基金
国家自然科学基金(60678010)资助
