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Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Infrared photodetectors in heterostructure nanowires
H Pettersson1, J Trägårdh, A I Persson
1Center for Applied Mathematics and Physics, Halmstad University, Box 823, SE-301 18 Halmstad, Sweden. Hakan.Petterson@ide.hh.se
Nano Letters
|February 9, 2006
Summary
Single nanowire heterostructures made of indium arsenide (InAs) and indium arsenide phosphide (InAsP) show potential for infrared photodetectors. These structures exhibit a strong polarization-dependent photocurrent, making them suitable for nanoscale polarization-sensitive applications.
Area of Science:
- Semiconductor Nanostructures
- Optoelectronics
- Materials Science
Background:
- Self-assembled nanowire heterostructures offer unique properties for electronic and optoelectronic devices.
- Indium arsenide (InAs) and indium arsenide phosphide (InAsP) are key materials in infrared optoelectronics.
Purpose of the Study:
- To investigate the photocurrent properties of single InAs/InAsP nanowire heterostructures.
- To evaluate their potential as nanoscale infrared polarization-sensitive photodetectors.
Main Methods:
- Fabrication of InAs/InAsP nanowire heterostructures using self-assembly.
- Characterization using spectrally resolved photocurrent measurements.
- Determination of material composition via energy-dispersive spectroscopy in transmission electron microscopy.
- Fabrication of Ohmic contacts using e-beam lithography.
Main Results:
- Spectrally resolved photocurrent measurements revealed threshold energies of ~0.65 eV and ~0.82 eV for different phosphorus compositions.
- A significant conduction band offset between InAs and InAsP effectively eliminated dark current at low temperatures.
- A strong polarization dependence was observed, with photocurrent being an order of magnitude higher for light polarized parallel to the nanowire.
Conclusions:
- Single InAs/InAsP nanowire heterostructures exhibit promising characteristics for infrared detection.
- The observed polarization sensitivity suggests their suitability for nanoscale infrared polarization-sensitive photodetectors.
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