Highly Sensitive Photodetector Using Ultra-High-Density 1.5-μm Quantum Dots for Advanced Optical Fiber Communications

Toshimasa Umezawa, Kouichi Akahane, Naokatsu Yamamoto, Atsushi Kanno, Tetsuya Kawanishi

Research output: Contribution to journalArticle

11 Citations (Scopus)


We have fabricated a high-density 1.5-μm quantum dot photodetector for advanced optical fiber communications and have found unique optical properties, including avalanche multiplication. The structure of the absorption layer had stacked InAs/InGaAlAs layers with a high density of 1 × 1012 cm-2, which consisted of strained 1.5-μm InAs quantum dots and a strain compensation layer of InGaAlAs. A three times larger absorption coefficient than the InGaAs layer, an avalanche multiplication effect, and a low dark current are reported with InAs quantum dot conditions.

Original languageEnglish
Article number6808407
JournalIEEE Journal on Selected Topics in Quantum Electronics
Issue number6
Publication statusPublished - 2014 Nov 1
Externally publishedYes



  • Avalanche photodiodes
  • optical fiber communications
  • photodetectors
  • quantum dots (QDs)

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Atomic and Molecular Physics, and Optics

Cite this