Presentation on theme: "PHOTONIC NANOSTRUCTURES WITH CONTROLLABLE AND MULTIFUNCTIONAL PROPERTIES Simion Astilean Babes-Bolyai University Faculty of Physics Molecular Spectroscopy."— Presentation transcript:
PHOTONIC NANOSTRUCTURES WITH CONTROLLABLE AND MULTIFUNCTIONAL PROPERTIES Simion Astilean Babes-Bolyai University Faculty of Physics Molecular Spectroscopy Group Cluj-Napoca
Current challenge of nanofabrication To control: To control: the size, shape, composition, spatial organization and chemical (biological) function of nanostructures Artificial nanostructures meet biomolecules
Main points of our research Developing an experimentally inexpensive method of controlled nanofabrication: The method is based on self-assembling process and nanosphere lithography and is able to fabricate large-area of highly ordered and shape-size-controlled nanostructures. Fabrication of multifunctional photonic nanostructures: Periodic arrays of noble-metal nanoparticles, Periodic arrays of nanoholes in metallic films, Photonic crystals, Self-assemblies of functionalized polymer nanospheres, Etc. Using light (photons) to extract and process information on the nanoscale: Optical bio-chemo-sensing, Ultrasensitive spectroscopic analysis, Photonics application, Etc.
Work on progress
1. Drop ~120 L colloid soln. onto hydrophillic substrate. 2. Dry in oven, spheres self assemble at meniscus edge. Starting with self-assembly of polystyrene nanospheres
SEM pictures of self-assembled monolayer of polystyrene nanospheres Starting with self-assembly of polystyrene nanospheres
AFM and SEM pictures of self-assembled multi-layers of polystyrene nanospheres
1. Thermally evaporate layer of silver or gold onto the polystyrene nanosphere array. 2. Combining nanosphere lithography with Reactive Ion Etching (RIE) Using self-assemblies of polystyrene nanospheres as templates for nanolithography
1. Regular Arrays of Noble-Metal Nanoparticles 2. Regular Nanoscale Hole-Arrays in Noble-Metal Films Using self-assemblies of polystyrene nanospheres as templates for nanolithography
Photonics Properties of Regular Arrays of Noble- Metal Nanoparticles Optical response of noble metal nanoparticles is dominated by the Localized Surface Plasmon Resonance (LSPR). Large near-field enhancement relative to incident field. Tunable Optical Response by altering particle size, shape, environment and proximity.
Photonic Properties of Nanoscale Hole-Arrays in Metallic Films Periodic structure of hole- arrays enables coupling light to surface plasmon (SP) mode. Evanescent field emerges through holes and is coupled to radiative modes. Giant optical transmission of sub-wavelength apertures.
(C) Combining Nanosphere Lithography with Reactive Ion Etching (RIE) 2. Remove nanospheres leaving hexagonal array of holes in a metal film 1. Etch nanosphere array in an oxygen plasma
Nanostructures for optical chemo-bio-sensing applications Nanosized optical biosensors based on surface plasmons resonances (SPR) Metal Light Plasmon 100 nm Linker Biomolecule FG Biomedical applications Conventional instruments Advantages of this approach receptor-ligand interactions; DNA hybridization; enzyme-substrate interaction protein conformation studies label-free immunoassay; high-throughput screening in pharmaceutical industry; uses expensive sensor chips; limited reuse capacity; complex chemistry for ligand or protein immobilization nanostructured support is cheap and easily synthesize; can be coated with various proteins or protein-ligand complexes by charge adsorption; monitored in any UV-vis spectrophotometre;
Surface Plasmon Resonances
Controlling the propagation, emission and detection of light on the nanoscale Nanostructures for photonic applications Novel spectroscopic tools for ultrasensitive analysis Novel class of optical materials Novel light sources Single Molecules Spectroscopic Fingerprint Fluorescence decay control Surface Enhanced Raman Scattering (SERS) Surface Enhanced IR Absorption (SEIRA) Photonic Crystals Photonic Integrated Circuits Telecommunication Devices Zero-Threshold Lasers Single - Photon Light Sources Quantum Information Devices
Fluorescence Decay Control
Required techniques for fabrication, processing and characterization of nanostructures StructuralChemicalOpticalOther TEM AFM XRD Confocal optical microscopy Surface chemistry * Nanosphere synthesis and functionalization Bioconjugation and linkage UV-vis spectroscopy * Fluorescence spectroscopy and lifetime measurements Raman spectroscopy * (microRaman, SERS) Infrared spectroscopy * Reactive ion etching Metal film deposition Modeling and Computing techniques * RMN EPR * Our laboratory facilities
We are looking for partners… National 1. Centrul de Biologie Moleculara (Institutul de Cercetari Experimentale interdisciplinare al Univ Babes-Bolyai, Cluj-Napoca) 2. Laboratorul de Materiale Nanostructurate Avansate (INCDTIM, Cluj-Napoca) 3. Catedra de Macromolecule (Univ Tehnica Gh Asachi, Iasi) 4. Institutul National de Chimie Macromoleculara P. Poni (Iasi) 5. Centrul de Fizica Plasmei, (Facultatea de Fizica, Univ. Al I Cuza, Iasi)International 1.Prof Sigrid Avrillier, Lasers Physics Laboratories, Paris University and SOPRA, France 2.Prof Gerard Bidan, Laboratoire dElectrochimie Moleculaire et Structures des Interfaces, DRFMC, CEA, Grenoble, France. 3.Dr Anne Corval and Dr Patrice Baldeck, Laboratoire de Spectrometrie Physique, Univ Joseph Fourier Grenoble France 4.Prof Arnulf Materny, School of Engineering and Science, International University Bremen, Germany 5. Prof WL Barnes, School of Physics, University of Exeter, UK 6.Dr Gilad Haran, Single Molecule Laboratory,Weizmann Institute, Rehovot, Israel 7.Dr Victor Weiss, Optronic Center, ELOP Electrooptics Industries Ltd, Rehovot, Israel 8.Dr Peter Persephonis, University of Patras, Patras, Greece Groups already contacted and interested in this research
Conclusions and Perspectives This project develops an experimentally simple technique for controlling the fabrication of nanostructures. The fabricated nanostructures have a real potential for relevant biosensing, photonics and ultrasensitive spectroscopic applications. This method of nanofabrication could be extended to semiconductors, polymer, ceramics and magnetic materials.