New class of broadly tunable middle-infrared electrically pumped solid-state lasers

本研究的主要目标包括：全面研究在体和量子受限结构中，由于载流子碰撞和重组导致的载流子TM离子能量转移机制。用于电致发光和激光研究的TM掺杂II-VI结构的设计、制造和表征。电泵浦tm掺杂II-VI结构激光特性的综合研究与优化。基于过渡金属（TM）掺杂II-VI结构的电泵浦激光器的实现需要满足两个条件：(1)电流对主体的持续激励；（ii）从主体到中红外激光TM杂质的有效能量传递。第一个条件的可行性得到了寿命超过10,000小时的II-VI LED光源开发的支持。第二个条件可以通过载流子冲击能量转移或通过复合工艺来实现。我们设想，对载流子TM离子能量转移机制的理解和优化将显著提高载流子碰撞机制的能量转移效率，特别是通过体p-n结和量子限制结构中的重组过程激发TM离子。更广泛的影响：劳动力发展将涉及(i)将研究结果纳入阿拉巴马大学系统两个校区的四门课程，（ii）研究生培训，以及（iii）通过REU网站进行本科生研究。此外，正在研究的创新方法将导致低成本电泵宽可调谐中红外激光源的突破性进展，这将影响医疗，环境，科学和反恐应用。

The major objectives of the effort include the following: Comprehensive study of the mechanisms of carriers' TM ions energy transfer due to carrier impact and recombination in bulk and quantum confined structures. Design, fabrication, and characterization of TM doped II-VI structures for electroluminescence and laser studies. Comprehensive studies and optimization of lasing characteristics of electrically pumped TM-doped II-VI structures.Intellectual merit: For realization of electrically pumped lasers based on transition metal (TM) doped II-VI structures two conditions should be satisfied: (i) sustainable excitation of the host by electrical current; and (ii) effective energy transfer from the host to the mid-IR lasing TM impurity. The feasibility of the first condition is supported by development of II-VI LED sources with a lifetime exceeding 10,000 hours. The second condition can be achieved either via carrier impact energy transfer or via recombination processes. We envision that understanding and optimization of the mechanisms of carrier TM ions energy transfer will enable significant improvement in the efficiency of energy transfer for carrier impact mechanisms, and especially for TM ions excitation via recombination processes in bulk p-n junctions and in quantum confined structures. Broader impacts: The workforce development will involve (i) incorporation of findings into four courses taught to two campuses of the University of Alabama System, (ii) graduate student training, and (iii) undergraduate student research through REU site. In addition, the innovative approaches to be investigated will lead to ground-breaking advances for low-cost electrically pumped broadly tunable mid-IR laser sources which will impact medical, environmental, scientific, and counter-terrorism applications.