Large-format voltage-tunable dual-color midwavelength infrared quantum-well infrared photodetector focal plane array

Kaldirim M., Eker S. U., Arslan Y., TÜMKAYA U., BEŞİKCİ C.

IEEE PHOTONICS TECHNOLOGY LETTERS, vol.20, pp.709-711, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 20
  • Publication Date: 2008
  • Doi Number: 10.1109/lpt.2008.920026
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.709-711
  • Middle East Technical University Affiliated: Yes


We report a large-format (640 x 512) voltage-tunable quantum-well infrared photodetector (QWIP) focal plane array (FPA) for dual-color imaging in the midwavelength infrared (3-5 mu m) band. Voltage-tunable spectral response has been achieved through series connection of two eight-well stacks of AlGaAs-InGaAs epilayers grown by molecular beam epitaxy on GaAs substrate. The peak responsivity wavelength of the detectors is shifted from 4.1 mu m (color 1) to 4.7 mu m (color 2) as the bias is increased within the limit applicable by commercial read-out integrated circuits. The operability of the FPA is similar to 99.5% with noise equivalent temperature differences of similar to 60 and 30 mK (f/1.5) in color modes 1 and 2, respectively. To our knowledge, this is the first large-format voltage-tunable dual-color QWIP FPA reported for midwavelength thermal imaging.