UCL logo

UCL Discovery

UCL home » Library Services » Electronic resources » UCL Discovery

1300 nm wavelength InAs quantum dot photodetector grown on silicon.

Sandall, I; Ng, JS; David, JP; Tan, CH; Wang, T; Liu, H; (2012) 1300 nm wavelength InAs quantum dot photodetector grown on silicon. Opt Express , 20 (10) 10446 - 10452. Gold open access


The optical and electrical properties of InAs quantum dots epitaxially grown on a silicon substrate have been investigated to evaluate their potential as both photodiodes and avalanche photodiodes (APDs) operating at a wavelength of 1300 nm. A peak responsivity of 5 mA/W was observed at 1280 nm, with an absorption tail extending beyond 1300 nm, while the dark currents were two orders of magnitude lower than those reported for Ge on Si photodiodes. The diodes exhibited avalanche breakdown at 22 V reverse bias which is probably dominated by impact ionisation occurring in the GaAs and AlGaAs barrier layers. A red shift in the absorption peak of 61.2 meV was measured when the reverse bias was increased from 0 to 22 V, which we attributed to the quantum confined stark effect. This shift also leads to an increase in the responsivity at a fixed wavelength as the bias is increased, yielding a maximum increase in responsivity by a factor of 140 at the wavelength of 1365 nm, illustrating the potential for such a structure to be used as an optical modulator.

Type: Article
Title: 1300 nm wavelength InAs quantum dot photodetector grown on silicon.
Location: United States
Open access status: An open access publication
Language: English
Keywords: Absorption, Arsenicals, Germanium, Indium, Materials Testing, Microscopy, Electron, Transmission, Nanotechnology, Optics and Photonics, Photochemistry, Quantum Dots, Quantum Theory, Silicon, Surface Properties
UCL classification: UCL > School of BEAMS > Faculty of Engineering Science > Electronic and Electrical Engineering
URI: http://discovery.ucl.ac.uk/id/eprint/1348685
Downloads since deposit
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item