The proposed research seeks to develop terahertz quantum-cascade lasers (THz QCLs) that operate at high temperatures, specifically above 240 K, so that they can be conveniently cooled by thermoelectric coolers. Such a development will have a significant impact on the science and technologies in THz frequencies, where potential applications are promising in sensing, imaging, and communications.
Intellectual merit: The project will involve a considerable amount of design effort of quantum structures composed with various combinations of quantum wells. If an isolated quantum well can be viewed as a one-dimensional "artificial atom", then a multiple quantum-well (MQW) structure is an "artificial molecule". This project is nothing short of designing and making such artificial molecules which perform the desired function of THz lasers. The principal investigator has the best track record in the field and has access to all the necessary facilities to carry out the proposed research activities.
Broader impacts: The principal investigator has been invited to give invited/plenary/keynote talks at many prestigious conferences. The work has also been reported in media for broad communities such as Technology Review, Laser Focus, NPR Market Place, Discovery, and Popular Science. Through collaborations, the THz lasers developed in the PI's group have helped to enhance infrastructures at other institutions in THz-related activities by adding a crucial enabling component. The principal investigator has incorporated elements in the research project into a graduate course in solid-state physics and a undergraduate core course Signals and Systems. Effort will be made to involve members from underrepresented groups and undergraduate students in the research activities.
