Mid-infrared quantum dot emitters utilizing planar photonic crystal technology.

Subramania,Ganapathi Subramanian ; Lyo, Sungkwun Kenneth ; Cederberg, Jeffrey George ; Passmore, Brandon Scott ; El-Kady, Ihab Fathy ; Shaner, Eric Arthur

Sandia National Laboratories

关键词: Optical Properties;    Design Planar Transisters.;    77 Nanoscience And Nanotechnology;    99 General And Miscellaneous//Mathematics, Computing, And Information Science;    Indium Arsenides;   

DOI  :  10.2172/966924
RP-ID  :  SAND2008-6217
RP-ID  :  AC04-94AL85000
RP-ID  :  966924

美国|英语

来源: UNT Digital Library

【 摘 要 】

The three-dimensional confinement inherent in InAs self-assembled quantum dots (SAQDs) yields vastly different optical properties compared to one-dimensionally confined quantum well systems. Intersubband transitions in quantum dots can emit light normal to the growth surface, whereas transitions in quantum wells emit only parallel to the surface. This is a key difference that can be exploited to create a variety of quantum dot devices that have no quantum well analog. Two significant problems limit the utilization of the beneficial features of SAQDs as mid-infrared emitters. One is the lack of understanding concerning how to electrically inject carriers into electronic states that allow optical transitions to occur efficiently. Engineering of an injector stage leading into the dot can provide current injection into an upper dot state; however, to increase the likelihood of an optical transition, the lower dot states must be emptied faster than upper states are occupied. The second issue is that SAQDs have significant inhomogeneous broadening due to the random size distribution. While this may not be a problem in the long term, this issue can be circumvented by using planar photonic crystal or plasmonic approaches to provide wavelength selectivity or other useful functionality.