室温Er∶YAG级联脉冲激光器的实验探究

Experimental Exploration of Er∶YAG Cascaded Pulsed Laser at Room Temperature

报道了室温下级联中红外Er∶YAG脉冲激光器。通过实验观测到级联发射的特征波长为1469 nm,确定了激发态吸收的特征波长为1676 nm。采用掺杂浓度(原子数分数)分别为7.5%和10%的两种Er∶YAG晶体,通过实验对比了级联与非级联条件下的中红外输出能量。掺杂浓度为7.5%的Er∶YAG中红外激光的最大单脉冲能量由非级联时的0.62 mJ提高至级联时的0.99 mJ,提高了约59.7%;掺杂浓度为10%的Er∶YAG中红外激光的最大单脉冲能量由非级联时的1.04 mJ提高至级联时的1.51 mJ,提高了约45.2%。实验结果表明,常温低掺杂Er∶YAG晶体可实现级联输出,并且级联有助于中红外激光单脉冲能量的提高。

Cascaded mid-infrared(MIR)Er∶YAG pulsed lasers at room temperature are reported.The characteristic wavelength of the cascaded emission is experimentally observed to be 1469 nm,and that of the excitedstate absorption is determined as 1676 nm.Er∶YAG crystals with doping concentrations(atomic number fractions)of 7.5%and 10%are adopted to compare the MIR output energy under the cascade and non-cascade conditions.For the Er∶YAG with a doping concentration of 7.5%,the maximum single pulse energy of MIR laser increases from 0.62 mJ(non-cascade)to 0.99 mJ(cascade),increasing by about 59.7%,and for Er∶YAG with a doping concentration of 10%,that increases from 1.04 mJ(non-cascade)to 1.51 mJ(cascade),increasing by about 45.2%.The experimental results confirm the existence of cascade output at room temperature in low-doped Er∶YAG crystals.The cascade is helpful to improve the single pulse energy of the mid-infrared laser.