EAGER: Development of novel wide-gap semiconductors for nuclear detection and IR photonics

Hampton University, Hampton VA

Investigators

Abstract

The National Science Foundation uses the Early-concept Grants for Exploratory Research (EAGER) funding mechanism to support exploratory work in its early stages on untested, but potentially transformative, research ideas or approaches. This EAGER project was awarded as a result of the invitation in the Dear Colleague Letter NSF 16-080 to proposers from Historically Black Colleges and Universities to submit proposals that would strengthen research capacity of faculty at the institution. The project at Hampton University aims to explore ternary metal halides for multi-functional applications, in particular for nuclear radiation detection and infrared solid-state gain media. If this project succeeds, it will result in the development of novel materials with improved functionalities for various applications and lead to significant industry impact. This project is co-funded by the Directorate for Mathematical and Physical Sciences. The development of wide-gap compound semiconductor crystals based on ternary metal halides is proposed for applications in nuclear radiation detection and infrared (IR) photonics. In this EAGER project, exploratory research will be performed on the material preparation and bulk crystal growth of metal halides. The proposed semiconductors will also be grown with rare earth dopants for applications in IR solid-state gain media. The work includes: the synthesis of candidate materials; purification studies and bulk crystal growth experiments; rare earth doping of purified crystals; and material characterization and modeling for applications in nuclear radiation detection and long-wavelength IR gain media. The exploratory and untested aspect of the proposed EAGER project lies in trying to combine the unique material properties of metal lead halides for two important applications with different physical mechanisms. Detailed studies on the role of defects and impurities on the optical and electrical properties of these materials will be performed as a function of temperature and elemental composition. Material purification and control of defect/impurity levels within the grown bulk crystals will be critical for deriving structure-property relations impacting possible device performance.