Topology: Photonics on the Edge

Andrea Blanco-Redondo

Engineering a material’s “topological phase” can enable robust light propagation that’s resistant to material defects—a possibility that’s opening new application domains in quantum photonics, integrated lasers and terahertz waveguides.

figureEdge-mode propagation and protection of entangled photons is one possible application of quantum topological photonics. [Illustration by Phil Saunders]

In 2005, F. Duncan M. Haldane at Princeton University, USA, with his student Srinivas Raghu, proposed that certain periodic arrangements of dielectric materials could support unidirectional propagation of light along the materials’ edges, with intrinsic immunity against back-reflections caused by imperfections. The prediction was a direct analogy with the quantum Hall effect realized in 1980 in a 2D electron gas.

Log in or become a member to view the full text of this article.

This article may be available for purchase via the search at Optica Publishing Group.
Optica Members get the full text of Optics & Photonics News, plus a variety of other member benefits.

Add a Comment