Hot Dot Detectors. Infrared Quantum Dot Intersubband Photodetectors Are a Promising Technology for Multiwavelength IR Detection
Abstract
This article presents the characteristics of a relatively new device, the quantum dot infrared (IR) photodetector, or QDIP. Recent advances in the epitaxial growth of strained heterostructures, such as Ga(In)As on GaAs, have led to the realization of coherent islands through the process of self-organization. These islands behave electronically as quantum boxes, or quantum dots. The first quantum dot laser was demonstrated almost a decade ago and since then other electronic and optoelectronic devices have been reported. Theoretical and experimental studies of scattering processes and hot carrier dynamics in the quantum dots indicate that the intersubband relaxation rate of the electrons are small and may even exhibit a phonon bottleneck, under weak excitation conditions. This property, together with the three-dimensional (3-D) carrier confinement and the near-discrete nature of the bound states, is ideal for the design of l o n g - w a v e l e n g t h intersubband detectors. Another advantage is the possibility of normal incidence operation due to the selection rules. The QDIP, therefore, has the potential of being a serious contender for applications in high-temperature IR detection, and significant progress has been made since its first demonstration nearly five years ago. The properties of these fascinating and important devices are described here. Some comparisons, in terms of dark current, are made with HgCdTe detectors and quantum-well IR photodetectors (QWIPs), two other successful technologies for IR detection.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2002
- Accession Number
- ADA596523
Entities
People
- A. D. Stiff-roberts
- J. D. Phillips
- P. Bhattacharya
- S. Krishna
- S. W. Kennerly
Organizations
- University of New Mexico