Nano-optomechanical nonlinear dielectric metamaterials

Abstract

Demonstration of a nearly ideal wavelength-selective optical mirror using a metamaterial-enabled dielectric coating Appl.

All-dielectric phase-change reconfigurable metasurface

“…[13][14][15][16][17] Active functionalities have been demonstrated on the basis of hybridization of a silicon metasurface with a liquid crystal, 18 two photon absorption on silicon metasurfaces 19,20 and nonlinear optomechanical reconfiguration in a free-standing silicon membrane metasurface. 21 By virtue of their compositionally-controlled high-index, low-loss characteristics, which extend over a broad spectral range from the visible to long-wave infrared, and can moreover be reversibly switched (electrically or optically) in a non-volatile fashion, the chalcogenides (binary and ternary sulphides, selenides, and tellurides) provide an exceptionally adaptable material base for the realization of optically reconfigurable meta-devices. Their phase-change propertiesreversible transitions between amorphous and crystalline states with markedly different optical and electronic properties-have been utilized for decades in optical data storage and more recently in electronic phase-change RAM.…”

Metamaterials at the University of Southampton and beyond

“…We predicted that it would exhibit a giant nonlinear optical response and nonlinear asymmetric transmission with a forward/backward optical extinction driven by resonant optomechanical forces in a structure comprised of dissimilar dielectric nanobars on a flexible membrane. As we have already noted above, we experimentally demonstrated highly nonlinear, dielectric, optomechanical metamaterials two years later [71], thereby offering a path to fast, compact and energyefficient all-optical metadevices. In 2016 we demonstrated an all-dielectric phase-change reconfigurable metasurface [102].…”

“…They can also be reconfigured by the light-induced forces that occur between elements of illuminated metamolecules. We have shown this in both plasmonic [70] and dielectric metamaterial nanostructures [71]. It is now clear that the nonlinear, switching, electro-optical and magneto-optical characteristics of nano-optomechanical metamaterials can surpass those of natural media by orders of magnitude.…”

“…Such a high level of nonlinearity allows for cross-wavelength, all-optical signal modulation with conventional telecom diode lasers of only a few milliwatts. Importantly, nanoscale metamaterial building blocks can be moved very fast, potentially offering gigahertz bandwidth switching, with modulation at a hundred MHz already having been achieved [71]. The first generation of randomly accessible, reconfigurable photonic metasurfaces on nanomembranes, providing control in a single spatial dimension, has also been realized [65].…”

“…We also demonstrated that dielectric metamaterials can be written, erased and rewritten as two-dimensional binary or greyscale patterns into a nanoscale film of phase-change material by inducing a refractive-index-changing phase transition with tailored trains of femtosecond pulses [51]. In collaboration with Professor Brian Hayden from Southampton's Department of Chemistry -a pioneer and global leader in the field of 'high-throughput materials discovery'-and colleagues in Singapore, we continue to explore new plasmonic and dielectric materials including chalcogenides, superconductors, topological insulators [71] and perovskites [103].…”