Organic-based polarisation detector promises fast measurement with low error

They believe that devices based on their technology could be faster and more accurate than current polarisation measurement techniques, which use devices based on silicon technology.

Polarisation is determined by the direction in which the electrical component of the electromagnetic field we perceive as light oscillates. Plane-polarised light – in which the field of a whole light-stream oscillates in the same direction - has many uses; because its polarisation affects how it bounces off objects, it can show up disturbed ground when searching or buried objects and can be used in atmospheric monitoring and medicine, for example.

The North Carolina team, led by Michael Kudenov, used a polymer known as P3HT:PCBM in their research; when this polymer is stretched, the backbones of the polymer chains all orient in one direction, and it absorbs polarised light whose oscillation is parallel to that direction and produces a photoelectric current.

Kudenov’s team, which explains its results in the journal Optical Express, made semi-transparent polymer films and placed them into a stack of materials with transparent gold film and indium tin oxide, stacked them together so that their alignment directions were all different.