Engineered nanostructure transforms polarisation state of light

It is claimed that the engineered surface, which consists of a periodic array of strongly coupled nanorod resonators, could improve systems that perform optical characterisation in scientific devices, such as ellipsometers; sensing, such as biosensing of proteins; or satellite communications.

‘We have designed and fabricated a waveplate that can transform the polarisation state of light,’ said Zhi Hao Jiang, a postdoctoral fellow in electrical engineering and lead author of a paper describing the research in Scientific Reports. ‘Polarisation is one of the most fundamental properties of light. For instance, if we transform linearly polarised light into circularly polarised light, this could be useful in optical communication and biosensing.’

According to the Pennsylvanian university, optical waveplates with broadband polarisation conversion over a wide field of view are highly sought after. Conventional waveplates have difficulty achieving broadband and wide-angle conversion. Thin waveplates have been demonstrated, but their efficiency was low, with an average power efficiency of less than 50 per cent.