Photoconducting liquid crystals

Abstract Major recent advances : ‘High’ mobility photoconduction in the columnar mesophases of disc-shaped (discotic) liquid crystals in which the charge carriers are holes or electrons was discovered in 1995. Prior to this photoconduction in liquid crystals was attributed to photo-generated ions and associated with ‘low’ mobilities. Over the last 7 years our understanding of the mechanism of carrier generation and transport in these novel, self-assembling systems has progressed to the point where we are able to design and manufacture organic semi-conductors with well-defined electronic and physical properties. Serious commercial devices incorporating conducting liquid crystals are finally on the horizon.

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