The multitude of properties present in carbon nanotubes makes them ideal for use in optoelectronic components.
Carbon-nanotubes as Ultrafast Photodetectors
In an attempt to influence and analyze their electronic and optic properties, a research team at the Technische Universitaet Muenchen headed by Prof. Alexander Holleitner has successfully developed a measurement process that enables time-based resolution of the photocurrent within the photodetectors with picosecond precision.
Professor Alexander Holleitner explained that the measurement technique used by them speeds the process by 100X as compared to other existing methods. This fast technique allows the measurement of the exact speed of electrons. Within the carbon nanotubes, electrons can cover only 800 nm per picosecond. The speed of electrons was measured using a time-resolved laser spectroscopy, which works on a pump-probe technique. The electrons in the nanotube are excited using a laser pulse. By using a second laser, the scientists can observe and analyze the properties.
The analytic opportunities and insights achieved by the laser spectroscopy technique can be applied in advancement of optoelectronic components such as photo-switches, solar cells and nanoscale photodetectors.
Source: http://www.tum.de