title: Active Optical Metasurfaces Based on Defect-Engineered Phase-Transition Materials.
abstract: Active, widely tunable optical materials have enabled rapid advances in photonics and optoelectronics, especially in the emerging field of meta-devices. Here, we demonstrate that spatially selective defect engineering on the nanometer scale can transform phase-transition materials into optical metasurfaces. Using ion irradiation through nanometer-scale masks, we selectively defect-engineered the insulator-metal transition of vanadium dioxide, a prototypical correlated phase-transition material whose optical properties change dramatically depending on its state. Using this robust technique, we demonstrated several optical metasurfaces, including tunable absorbers with artificially induced phase coexistence and tunable polarizers based on thermally triggered dichroism. Spatially selective nanoscale defect engineering represents a new paradigm for active photonic structures and devices.
authors.affiliation: Institute for Solid State Physics, Friedrich-Schiller-Universität Jena , 07743 Jena, Germany.
authors.forename: Jura
authors.initials: J
authors.lastname: Rensberg
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Shuyan
authors.initials: S
authors.lastname: Zhang
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: You
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Physics, University of California - San Diego , La Jolla, California 92093, United States.
authors.forename: Alexander S
authors.initials: AS
authors.lastname: McLeod
authors.affiliation: Institute for Solid State Physics, Friedrich-Schiller-Universität Jena , 07743 Jena, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Schwarz
authors.affiliation: Department of Physics, University of California - San Diego , La Jolla, California 92093, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Goldflam
authors.affiliation: Department of Physics, University of California - San Diego , La Jolla, California 92093, United States.|Department of Physics, Stony Brook University , Stony Brook, New York 11794, United States.
authors.forename: Mengkun
authors.initials: M
authors.lastname: Liu
authors.affiliation: Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf , 01328 Dresden, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Kerbusch
authors.affiliation: Institute for Solid State Physics, Friedrich-Schiller-Universität Jena , 07743 Jena, Germany.
authors.forename: Ronny
authors.initials: R
authors.lastname: Nawrodt
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States.|School of Materials Engineering, Purdue University , West Lafayette, Indiana 47907, United States.
authors.forename: Shriram
authors.initials: S
authors.lastname: Ramanathan
authors.affiliation: Department of Physics, University of California - San Diego , La Jolla, California 92093, United States.
authors.forename: D N
authors.initials: DN
authors.lastname: Basov
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Federico
authors.initials: F
authors.lastname: Capasso
authors.affiliation: Institute for Solid State Physics, Friedrich-Schiller-Universität Jena , 07743 Jena, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Ronning
authors.affiliation: John A. Paulson School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States.
authors.forename: Mikhail A
authors.initials: MA
authors.lastname: Kats
keywords: Metasurfaces; defect engineering; meta-devices; metamaterials; phase-transition materials