Thermoelectric and optoelectronic devices

Overview This proposal aims to build up new ties between Princeton University (PU) and the University of São Paulo (USP) in order to explore innovative semiconductor devices. The focus of the project is to create an interaction between the groups in the development of new semiconductor devices. The collaborative research will be based in the growth and characterization of thermoelectric materials and of high-performance optoelectronic devices based on III-V nanostructures such as quantum cascade lasers (QCLs), quantum cascade detectors (QCDs), quantum well infrared photodetectors (QWIPs), and quantum dot infrared photodetectors (QDIPs). These devices can be used in infrared cameras and gas sensing systems that have many practical applications related to agriculture, engineering, public health, energy management, environmental conservation, defense, etc. One branch of the proposal lies on the development of new semiconductor heterostructures in order to study the heat and electrical propagation in the pursuit of a more efficient thermal energy harvester. The innovation envisioned is on the use of self-assembled quantum dots to create a restraint in the phonon propagation, diminishing the conduction of high frequency phonons and creating an approach to treat heat propagation as waves. The treatment of heat transport as waves, instead of diffusive, allows the realization of completely new devices, i.e., heat waveguides, diodes for heat, heat lenses and thermal cloaking. Another branch is focused on the development and improvement of infrared solid-state lasers and photodetectors that are the main research topics at Princeton and São Paulo, respectively. The group at Princeton is known worldwide for its research about QCLs, and would like to gain experience in the growth of quantum dots. The group at São Paulo has a extensive experience with quantum dots, quantum wells and related infrared detectors, and would like to take advantage of Princeton's experience to start producing QCLs and integrated QCL-QCD devices. It is the first time that both groups will interact, but it is obvious from their background that this partnership will tremendously improve their respective expertise by sharing their complementary know-how on these topics. Dr. Germano Penello, who was recently granted a post-doctoral fellowship in Princeton's group, is familiar with both groups, and therefore will be the initial bridge between both. Several faculty members and students are expected to travel and visit the partner group every year and will receive full support to develop their activities on both sides. Short-, medium-and long-term programmatic goals have been established in …