Optical devices create, guide, and detect electromagnetic waves and include lasers, telescopes, and solar cells. Most of the materials used in these devices are challenging for certain applications because of a phenomenon known as optical reciprocity, an inherent symmetry which forces light to travel bidirectionally. One example of an application-based challenge is a high-powered laser, where back-scattered light caused by optical reciprocity can damage the instrument.
Click here for original story, Researchers discover new topological phases in a class of optical materials
Source: Phys.org