All-dielectric phase-change reconfigurable metasurface
  We harness non-volatile, amorphous-crystalline transitions in the chalcogenide phase-change medium germanium antimony telluride (GST) to realize optically-switchable, all-dielectric metamaterials. Nanostructured, subwavelength-thickness films of GST present high-quality resonances that are spectrally shifted by laser-induced structural transitions, providing reflectivity and transmission switching contrast ratios of up to 5:1 (7 dB) at visible/near-infrared wavelengths selected by design. 
Artemios Karvounis, Behrad Gholipour, Kevin F. MacDonald, and Nikolay   I. Zheludev
cond-mat.mes-hall physics.optics