Meta-materials offer potential for sensitive hydrocarbon detectors

Research at Duke University in North Carolina has led to the development of meta-materials that simplify the construction of sensors to detect characteristic infrared signatures from hydrocarbon molecules. The sensors will be capable of detecting infrared signatures even while moving.

The Duke team, working with optoelectronics materials company SRICO, believes that these detectors are smaller, lighter, faster, more powerful and cheaper than currently available technology.

In a paper in the journal Optica, the team explains how it constructed the sensor by layering a pattern of pure gold on top of a slice of crystalline lithium niobate. This is a pyroelectric material, that is, it generates a charge when it gets hot. The crystal slices, some 600nm thick, were prepared by SRICO engineers using an ion beam to peel off the slices from a larger crystal. The top layer of the gold is treated so that it only allows a few specific frequencies of infrared radiation through to the crystal; the metal also conducts the charge generated by the warmed niobate into an amplifier to produce a visible signal in a detector.