Mid-infrared Semiconductor Lasers Based on Intersubband Transitions in the Valence Band of GaAs/AlAs Quantum Cascade Nanostructures

Purdue University, West Lafayette IN

Investigators

Abstract

ECCS-0725384 O. Malis, SUNY Binghamton Intellectual merit: This project will investigate a new class of mid-infrared quantum cascade lasers based on Carbon-doped GaAs/AlAs nanostructures. Unlike traditional quantum cascade lasers, the proposed devices utilize hole transport and intra-valence band transitions. The major objective is to exploit the unique optical properties of hole intersubband transitions to demonstrate surface-emitting lasing in the 5-10 um range. The approach will be multi-pronged, experimental and theoretical. Hole cascaded structures will be designed, grown, and characterized. The project will focus on enhancing the understanding of the physics of hole intersubband transitions and of ultrafast hole relaxation processes in the context of a well developed semiconductor system where material quality issues are minimized. Nevertheless, the acquired knowledge will also provide invaluable insights into the prospects of infrared laser light emission in other material systems, most notably in Si/SiGe, GaN, and ZnSe. This investigation will also advance the understanding of basic mechanisms involved in molecular beam epitaxy of nanostructures and in growth of high-purity Carbon-doped GaAs. Broader Impact: The proposed new device concept for mid-infrared laser emission is expected to significantly impact spectroscopic techniques for in-situ and remote trace gas sensing. Mid-infrared surface emitting lasers would enable integration of several sensors on a single chip for simultaneous detection of several gasses with immediate benefits for applications in air quality control, health monitoring, or explosive detection. This project will also offer graduate and undergraduate students at SUNY-Binghamton unique opportunities to integrate education, training and research in both the academic and industrial research environments. Particular attention will be given to enhancing the opportunities of under-represented groups in science and engineering. The faculty and graduate students will engage in outreach activities targeted at introducing material science and technology to high-school and non-science major students, as well as to the general public. A hands-on lab-based course on the fundamental and practical aspects of nanoscale science and engineering will be developed.