A team of electrical engineers from Penn State University in the US has developed a device featuring a single layer of metallic nanostructures and says the device provides 'exceptional capabilities' for manipulating light. Applications potentially include satellite communications.
"We have designed and fabricated a waveplate that can transform the polarisation state of light," said post doctoral fellow Zhi Hao Jiang. "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."
While thin waveplates have been demonstrated previously, they had an average power efficiency of less than 50%. Penn State's nanofabricated waveplate is said to achieve polarisation conversion rates of more than 92% over a bandwidth of more than an octave and with a 40° field of view.
"We demonstrated with simulation and experiment both quarter- and half-waveplate metasurfaces that operate in the visible spectrum as well as in the near infrared," said researcher Jeremy Bossard. "It also has a wide field of view, which means that if you illuminate the surface from a wide range of angles, it would still give the same reflective performance." A wider field of view can reduce the number of optical components in a system and achieve wide broadband functionality in the visible to near infrared wavelength range.
Author
Graham Pitcher
Source: www.newelectronics.co.uk