Princeton engineers make breakthrough in ultrasensitive sensor
technology Posted March 28, 2011; 01:30 p.m. Princeton
researchers have invented an extremely sensitive sensor that
opens up new ways to detect a wide range of substances, from
biological markers of cancer to hidden explosives. The sensor,
which is the most sensitive of its kind to date and easy to
produce, relies on a completely new architecture and fabrication
technique developed by the Princeton researchers. The device
boosts faint signals generated by the scattering of laser light
from a material placed on the sensor, allowing the
identification of various substances based on the color of light
they reflect. The sample could be as small as a single molecule.
The technology is a major advance in a decades-long search to
identify materials using Raman scattering, a phenomenon
discovered in the 1920s by Indian physicist Chandrasekhara
Raman, in which light reflecting off an object carries a
signature of its molecular composition and structure. Pr