Uncooled, High-Efficiency Mid-Infrared Lasers by Using Intersubband Quantum-Box Structures

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

The objective of the proposed work is to demonstrate devices that utilize intersubband transitions in arrays of quantum boxes (QBs), to achieve room-temperature, continuous-wave (CW) oscillation in the mid-infrared (IR) wavelength range, with low heat-dissipation powers. Intellectual Merit: The novel approaches proposed are: 1) the use of block-copolymer lithography for the realization of arrays of 20-25 nm-diameter QBs; 2) the use of deep quantum wells for the QB active material for strong carrier confinement; 3) the use of selective regrowth of high-bandgap barriers to confine carriers in the plane of the QBs.. Broader Impacts: The realization of uncooled, CW mid-IR sources will make possible hand-held, real-time sensors for a wide range of noninvasive medical diagnostics and enable exciting developments such as practical sensing of chemical agents and explosives. A central goal and natural outcome of this project is the research-based education of both undergraduate and graduate students. The students will be involved in all aspects of the research within an established collaborative team-based environment. The proposed program provides opportunities for outreach to underrepresented groups through our ongoing partnering with the existing college and NSF Center-based programs at the University of Wisconsin. The realization of the proposed QB lasers will have a transformational impact on both the science and technology of mid-IR lasers because reducing the heat dissipation by two orders of magnitude will lead to uncooled devices, which in turn will revolutionize the mid-IR sensors industry since hand-held sensors would become available for a vast array of applications.