Optically imprinted reconfigurable photonic elements in a VO2 nanocomposite

T. Jostmeier, J. Zimmer, H. Karl, H. J. Krenner, M. Betz

Applied Physics Letters 105, 071107 (2014) DOI: Applied Physics Letters

We investigate the optical and thermal hysteresis of single-domain vanadium dioxide nanocrystalsfabricated by ion beam synthesis in a fused silica matrix. The nanocrystals exhibit a gianthysteresis, which permits to optically generate a long-time stable supercooled metallic phase persistent down to practically room temperature. Spatial patterns of supercooled and insulatingnanocrystals feature a large dielectric contrast, in particular, for telecom wavelengths. We utilize this contrast to optically imprint reconfigurable photonic elements comprising diffraction gratingsas well as on- and off-axis zone plates. The structures allow for highly repetitive (>104) cycling through the phase transition without structural damage.