Freezing liquid inside optical fibre makes light and sound interact 1,000x more

Freezing liquid inside an optical fibre has helped scientists create an unusual environment where light and sound can interact more than 1,000 times more strongly than they do in ordinary optical fibres.According to Science Daily, scientists from the Max Planck Institute of the Science of Light (MPL) in Erlangen, Leibniz University Hannover (LUH) and the Leibniz Institute for Photonic Technologies (IPHT) in Jena, cooled the liquid inside a special optical fibre to -196°C using nitrogen.The extreme cold changed the material in the fibre’s core from a liquid into a solid. The surprising part was that freezing the liquid did not stop the fibre from guiding light. The researchers also found that both the liquid and frozen sections of the fibre could guide hypersonic sound waves.The team used this effect to demonstrate optoacoustic memory.