高效中红外激光晶体Cr,Er,Re:YSGG（Re＝Eu3+, Tb3+）的生长及性能研究

2.7-3 μm mid-infrared laser has broad application prospects in the fields of medicine, biotechnology, infrared laser radar and defense security, is one of most scarce and urgent need laser sources. Er3+ ions are important rare earth ions in realizing this waveband laser. However, its lifetime of laser low level 4I13/2 is usually longer than that of the laser upper level 4I11/2, which is unfavorable for the population inversion, so the continuous and efficient mid-infrared laser output has been influenced. In this project, We propose that the Eu3+ or Tb3+ ions are doped into Cr,Er:YSGG crystal, to use the resonance energy transfer between Er3+ and Eu3+ or Tb3+ ions, to speed up the particle evacuating rate of laser lower level 4I13/2 and reduce its lifetime in order to achieve 2.7-3μm laser with high efficiency, to promote the application of the crystal and laser components in laser medicine and defense security. Therefore, this project has important scientific significance and practical value.

2.7～3微米中红外激光在医疗、生物技术、红外激光雷达和国防安全等领域有着广阔的应用前景，是目前最缺乏和急需的光源波段之一。Er3+离子是产生该波段激光的重要稀土离子，但其激光下能级4I13/2的寿命通常比激光上能级4I11/2长，不利于粒子数反转，因此其连续、高效的中红外激光发射受到了影响。本项目提出在Cr,Er:YSGG中掺入Eu3+、Tb3+等离子，利用Er3+与Eu3+、Tb3+离子之间共振能量传递，加快激光下能级4I13/2的粒子抽空速率，减小其寿命，从而实现2.7～3微米波段高效的中红外激光输出，促进其晶体及激光元件在激光医疗和国防安全等领域中的应用。因此，本项目的研究具有重要的科学意义和实际应用价值。

2.7~3微米中红外激光在生物医疗、红外激光雷达和国防安全等领域有着广阔的应用前景，因此高效2.7~3微米激光晶体材料的研究有着重要的科学意义和应用价值。Er3+离子是产生该波段激光的重要稀土离子，但其激光下能级4I13/2的寿命较长，不利于实现高效率及高重复频率的激光输出。我们选择掺入少量的Eu3+、Tb3+、Ho3+、Pr3+作为能级耦合离子，对其能级耦合效率进行了研究，优化出了能级耦合及激活离子的掺杂浓度，有效降低了下能级4I13/2的寿命。采用提拉法成功生长出了高质量的Cr,Er,Eu:YSGG、Cr,Er,Ho:YSGG及Cr,Er,Pr:GYSGG晶体，系统研究了晶体的热学及光谱等性能, 测试表明Cr,Er,Ho:YSGG及Cr,Er,Pr:GYSGG晶体在2.79微米处的最大发射截面显著优于Er:YSGG。采用闪光灯或LD泵浦，对晶体的激光性能进行了系统研究，实现了最高4.7W的2.79微米激光输出，结果表明，通过能级耦合离子Ho3+、Pr3+的掺入，可以较好地提升晶体在高重复频率下的激光性能。本项目的研究为该类晶体在高重复频率领域的应用奠定了良好的基础。