Programmable hyperbolic polaritons in van der Waals semiconductors
Aaron Sternbach, Sang Hoon Chae, Simone Latini, Andrey Rikhter, Yinming Shao, Baichang Li, Daniel Rhodes, B. Kim, P. James Schuck, Xiaodong Xu, Xiaoyang Zhu, Richard D. Averitt, James Hone, M. M. Fogler, Ángel Rubio, D. N. Basov
Abstract
Lighting a route for hyperbolic dispersion The propagation of light within a material is usually well defined, with the propagation described by scattering and dispersion. In artificially designed metamaterials and in anisotropic layered materials, the dispersion can be hyperbolic, giving rise to subwavelength confinement of the light. Sternbach et al. show that the hyperbolic dispersion can be optically switched on and off on demand in the layered transition metal dichalcogenide tungsten diselenide (see the Perspective by Deng and Chen). Illuminating the material with ultrafast pulses of sub-bandgap light creates a transient waveguide, resulting in hyperbolic dispersion in the material. The ability to tune the dispersion characteristics on demand using optical pumping is an effective approach for developing ultrafast switching photonic devices and controlling the propagation of light on the nanoscale. Science , this issue p. 617 ; see also p. 572