title: Multiple-junction quantum cascade photodetectors for thermophotovoltaic energy conversion.
abstract: The use of intersubband transitions in quantum cascade structures for thermophotovoltaic energy conversion is investigated numerically. The intrinsic cascading scheme, spectral agility, and design flexibility of these structures make them ideally suited to the development of high efficiency multiple-junction thermophotovoltaic detectors. A specific implementation of this device concept is designed, based on bound-to-continuum intersubband transitions in large-conduction-band-offset In(0.7)Ga(0.3)As/AlAs(0.8)Sb(0.2) quantum wells. The device electrical characteristics in the presence of thermal radiation from a blackbody source at 1300 K are calculated, from which a maximum extracted power density of 1.4 W/cm(2) is determined. This value compares favorably with the present state-of-the-art in interband thermophotovoltaic energy conversion, indicating that quantum cascade photodetectors may provide a promising approach to improve energy extraction from thermal sources.
authors.affiliation: Department of Electrical and Computer Engineering and Photonics Center, Boston University, Boston, MA 02215, USA.
authors.forename: Jian
authors.initials: J
authors.lastname: Yin
authors.forename: Roberto
authors.initials: R
authors.lastname: Paiella
mesh_terms: D017076:Computer-Aided Design; D011211:Electric Power Supplies; D004581:Electronics / Q000295:instrumentation*; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006358:Hot Temperature; D010783:Photometry / Q000295:instrumentation*; D045663:Quantum Dots; D011789:Quantum Theory