A multicolor, broadband (5-20 mu m), quaternary-capped InAs/GaAs quantum dot infrared photodetector

作者：Adhikary Sourav; Aytac Yigit; Meesala Srujan; Wolde Seyoum; Perera A G Unil; Chakrabarti Subhananda^*

来源：Applied Physics Letters, 2012, 101(26): 261114.

DOI：10.1063/1.4773373

An InAs/GaAs quantum dot infrared photodetector with strong, multicolor, broadband (5-20 mu m) photoresponse is reported. Using a combined quaternary In0.21Al0.21Ga0.58As and GaAs capping that relieves strain and maintains strong carrier confinement, we demonstrate a four color infrared response with peaks in the midwave-(5.7 mu m), longwave-(9.0 and 14.5 mu m), and far-(17 mu m) infrared regions. Narrow spectral widths (7% to 9%) are noted at each of these wavelengths including responsivity value similar to 95.3mA/W at 14.5 mu m. Using strain field and multi-band k.p theory, we map specific bound-to-bound and bound-to-quasibound transitions to the longwave and midwave responses, respectively.

• 出版日期2012-12-24