RUI: Investigation of Spectroscopic and Laser Properties of Rare Earth Ions in Crystalline Laser Hosts Using High Resolution Spectroscopic Techniques

9303448 Sardar本基金的研究目的是利用激光光谱学技术研究稀土离子掺杂在晶体主体材料中的光学特性。两种重要的钕基单晶：YVO4:Nd3+(1%)和CaMgZnY2Ge3012:Nd3+(2%)将首先进行研究。对第一种材料有一些研究，但对第二种材料没有研究。在项目的最后阶段，将研究更复杂的三掺杂材料：YAG: Cr3+ (1%), Tm3+ (5%), Ho3+(1%)。将对这些材料进行全面系统的光谱研究，将其光学和激光特性与现有激光材料进行比较，并评估这些材料作为激光器的潜力。测量将包括在不同温度下的吸收、发射、激发光谱和荧光寿命。这些材料近年来受到了广泛关注，因为它们的发射波长在2um范围内，由于该波长的强吸水性，已被证明对许多医疗应用非常有吸引力。Ho3+中的2.1um 5I7 - 5I8激光跃迁具有吸引力，因为它的上能级寿命长，约为5 ms，比Nd:YAG允许更大的能量存储，并且具有人眼安全的波长。研究该晶体中从Cr3+到Tm3+再到Ho3+的能量转移的重要机制，将为参与该项目的本科生提供良好的教育经验；该资助是美国国家科学基金会本科院校研究（RUI）活动的一部分。这项工作是当前光子学领域的一个科学兴趣领域，在技术上是相关的，并且有很好的潜力为参与的本科生提供一个有价值的教育机会，他们将接触到现代光谱设备、技术和理论。＊＊＊

9303448 Sardar Research on this grant aims to investigate the optical properties of rare earth ions doped in crystalline host materials using the techniques of laser spectroscopy. Two important neodymium-based single crystals: YVO4:Nd3+ (1 %) and CaMgZnY2Ge3012:Nd3+ (2%) will be studied initially. There have been some studies on the first material, but none on the second. In the final phase of the project, a more complex, triply-doped material: YAG: Cr3+ (1%), Tm3+ (5%), Ho3+ (1%) will be investigated. A complete and systematic spectroscopic investigation of these materials will be performed, their optical and laser properties will be compared with those of existing laser materials, and the potential of these materials as lasers will be evaluated. The measurements will include absorption, emission, and excitation spectra and fluorescence lifetimes at different temperatures. %%% These materials have received much attention in recent years since their emission wavelength falls in the 2um range, which has proven to be very attractive for a number of medical applications because of the strong water absorption at this wavelength. The 2.1um 5I7 - 5I8 laser transition in Ho3+ is attractive because of its long upper laser level lifetime, of the order of 5 ms, permitting larger energy storage than Nd:YAG, and its eye-safe wavelength. Study of the important mechanism of energy transfer from Cr3+ to Tm3+ and finally to Ho3+ in this crystal will provide an excellent educational experience for undergraduates involved in the project; this grant is part of NSF's Research in Undergraduate Institutions(RUI) activity. The proposed work is in an area of current scientific interest in the field of photonics, is technologically relevant, and has excellent potential to provide a rewarding educational opportunity for the participating undergraduates who will be exposed to modern spectroscopic equipment, techniques, and theories. ***