Two-step excitation unlocks and steers exotic nanolight

An international team of researchers has developed a novel technique to efficiently excite and control highly-confined light-matter waves, known as higher-order hyperbolic phonon polaritons. Their method not only sets new records for the quality and propagation distance of these waves but also uses a sharp boundary to create a form of pseudo-birefringence, sorting and steering the waves by mode into different directions.