Scientists find new role for the swastika

Just a month after a call for a European-wide ban of the swastika, scientists have found that the symbol has new applications in optical communications and could have a role in quantum cryptography.

Dr Darren Bagnall from the School of Electronics and Computer Science (ECS) at the University of Southampton has found that he can arrange tens of thousands of gold swastikas on a square millimetre to form new optical metamaterials that act to artificially change the polarisation of light, effectively “twisting” light in accordance with the rotation of the swastikas. By changing the degree of twist in a predictable way the chiral metamaterials can provide an alternative way to code information that is being transmitted using light.

According to Dr Bagnall, it is the special arrangement and squareness of the swastika which makes it the ideal geometry for their experiments. He comments: “The swastika has a number of special features, it is entirely made up of vertical and horizontal straight lines and it is square but can still provide the feeling of left-handed or right-handed rotation known as chirality. It is this chirality which causes our swastikas to twist light.”

Dr Bagnall and his team are continuing to experiment with a wide range of other chiral geometries such as, spirals, triskella and some fractals and are very excited about the potential for use of these chiral metamaterials in technology.

Dr Bagnall comments: ‘While we are still at an early stage in our experiments, we can already anticipate applications in optoelectronics, laser physics and optical communications. This is especially true, as technologists are increasingly using polarisation state as a means of carrying information in applications such as quantum cryptography.’