Georgia Institute of  Technologystripes
Titania inverse opalGroup photo in front of the Love BuildingWhite LEDs

NANOPHOTONICS

NEWS & EVENTS

Several of our publications were selected for the Virtual Journal of Nanoscale Science & Technology:
November 13 (2006): "Photonic band tuning in two-dimensional photonic crystal slab waveguides by atomic layer deposition,"
Appl. Phys. Lett. 89,181108 (2006).

March 6 (2006): "Photoluminescence modification by high-order photonic bands in TiO2/ZnS:Mn multilayer inverse opals,"
Appl. Phys. Lett. 88, 081109 (2006).

December 26 (2005): "Electric-field tuning of the Bragg peak in large-pore TiO2 inverse shell opals,"
Phys. Rev. B. 72, 233105 (2005).

November 21 (2005): "Photonic bandgaps in highly conformal inverse opal based photonic crystals,"
Phys. Rev. B. 72, 205109 (2005).

A publication was selected for the Virtual Journal of Biological Physics Research:
March 15 (2006): "ZnTe:O phosphors development for X-ray imaging applications,"
Appl. Phys. Lett. 88, 111904 (2006).


TiO2 nanobowl sheet technique selected for Editor's Choice in Science 309, 1790 (2005).

An image from our Nano Letters publication was used for Chemical & Engineering News, NanoFocus "Image of the Month."


Here is a PowerPoint summary of photonic crystal research in our group.

Here is a PowerPoint summary of atomic layer deposition (ALD) research in our group.

CONTACT INFORMATION

Christopher J. Summers

Professor, School of Materials Science & Engineering
Director, Phosphor Technology Center of Excellence
Erskine Love Jr., Building
771 Ferst Drive NW
Atlanta, GA 30332-0245
Phone: 404.894.0697
Email Chris Summers

School of Materials Science & Engineering Georgia Institute of Technology
771 Ferst Drive, NW
Atlanta, GA 30332-0245
Phone: (404) 894 - 8414
FAX: (404) 894 - 9140
Email: academic@mse.gatech.edu

The Nanophotonics research group at Georgia Tech is led by Prof. Chris Summers in the School of Materials Science & Engineering.

The groups research goals center on developing and characterizing new 2D and 3D photonic crystal (PC) materials and phosphors. Active areas of research include modeling and simulation of 2D and 3D photonic crystal structures using both the Plane Wave Expansion (PWE) and Finite-Difference Time-Domain (FDTD) methods. Experimentally, we have several members focused on fabricating inverse opal structures. Our primary method of opal infiltration is Atomic Layer Deposition (ALD), and we have built ALD reactors for oxide (TiO2, Al2O3, ...) and phosphide (GaP, InP, ...) thin film growth. We also have several students working on luminescent quantum dots and phosphors for incorporation into photonic crystal structures. More information about our research areas can be found by following the links below.

2D Photonic Crystals:

Our effort is directed to the design and fabrication of novel two-dimensional photonic crystals for controlling light. Currently we are pursuing new concepts to obtain very large and tunable refraction and dispersion properties, and to reduce beam divergence and to focus propagating beams.

3D Photonic Crystals:

Our primary thrust is to investigate and to develop novel wide photonic band gap three-dimensional PC architectures for generating and controlling light. A major focus of our effort is designing and fabricating inverse opal-based structures using atomic layer deposition and selective etching. Luminescent properties have been obtained by incorporating phosphor or QD materials into the structures and dynamical tuning by the infiltration of nematic liquid crystals. Recently, holographically defined polymer templates have been infiltrated and inverted by these techniques.

Conventional & Quantum Dot Phosphors:

New luminescent materials are being developed for displays, solid state lighting and X-ray imaging applications. Currently, non Cd-based technologies for solid state lighting are being developed based on III-V quantum dot (QD) materials that enable the whole visible spectral range to be covered. Also, coating techniques are being developed to control both QD size and surface recombination properties. Future work will be directed to the formation of core/shell structures and the synthesis of doped nano-particles. The investigation of X-ray phosphors is directed to the development of high efficiency ZnTe:O doped materials prepared by a dry synthesis method.

Nanotechnology & Spintronics:

In cooperation with Professor Wang's and Professor Ferguson's programs, the properties of ZnO nanowires, nanorods and nanobelts are being investigated and work is being performed on the development of spintronic materials and devices.

Atomic Layer Deposition:

New protocols for atomic layer deposition have been developed, primarily in support of the 3D photonic crystal program, which involves the infiltration of highly porous opal and holographically formed templates. Materials investigated include, TiO2, Al2O3, ZnO, ZnS:Mn and GaP and InP. Recent efforts include hermetically coating phosphors and related display material structures.

Recent Publications:

  1. "Enhanced tunable Bragg diffraction in large-pore inverse opals using dual-frequency liquid crystal,"
    E. Graugnard, S. N. Dunham, J. S. King, D. Lorang, S. Jain, and C. J. Summers, Appl. Phys. Lett. (in press).

  2. "Tunable Bragg peak response in liquid crystal infiltrated photonic crystals,"
    D.P. Gaillot and C.J. Summers, J. Opt. Soc. Amer. B 24, 7 (2007)

  3. "Photonic band gaps in non-close-packed inverse opals,"
    D. P. Gaillot and C. J. Summers, J. Appl. Phys. 100, 113118 (2006).

  4. "Photonic band tuning in two-dimensional photonic crystal slab waveguides by atomic layer deposition,"
    E. Graugnard, D. P. Gaillot, S. N. Dunham, C. W. Neff, T. Yamashita, and C. J. Summers, Appl. Phys. Lett. 89,181108 (2006).
    Selected for the Virtual Journal of Nanoscale Science & Technology, 14 November 13 (2006).

  5. "Luminescent and tunable 3D photonic crystal structures,"
    C.J. Summers, E. Graugnard, D. P. Gaillot, and J.S. King, J. Nonlinear Opt. Phys. Mater., 15, 203 (2006).

  6. "Polarization beam splitter based on a photonic crystal heterostructure,"
    E. Schonbrun, Q. Wu, W. Park, T. Yamashita, and C. J. Summers, Optics Letters 31 (21), 3104-6 (2006).

  7. "Negative index imaging by index-matched photonic crystal slab,"
    E. Schonbrun, T. Yamashita, W. Park and C. J. Summers, Phys. Rev. B 73, 195117, (2006).

  8. "Liquid-Crystals for optical filters, switches and tunable negative index material development,"
    I.C. Khoo, Y. Williams, A. Diaz, K. Chen, J. A. Bossard, L. Li, D. H. Werner, E. Graugnard, J. S. King, S. Jain, and C. J. Summers, Molecular Crystals and Liquid crystals, 453, 309 (2006).

  9. "Infiltration and inversion of holographically-defined polymer photonic crystal templates by atomic layer deposition,"
    J. S. King, E. Graugnard, O. M. Roche, D. N. Sharp, J. Scrimgeour, R. G. Denning, A. J. Turberfield, and C. J. Summers, Adv. Mater. 18, 1561 (2006).

  10. "Sacrificial-layer atomic layer deposition for fabrication of non-close-packed inverse opal photonic crystals,"
    E. Graugnard, J. S. King, D. P. Gaillot and C. J. Summers, Adv. Func. Mater. 16, 1187 (2006).

  11. "Conformally back-filled, non-close-packed inverse-opal photonic crystals,"
    J. S. King, D. Gaillot, E. Graugnard, and C. J. Summers, Adv. Mater. 18, 1063 (2006).

  12. "Photoluminescence modification by high-order photonic bands in TiO2/ZnS:Mn multilayer inverse opals,"
    J. S. King, E. Graugnard, and C. J. Summers, Appl. Phys. Lett. 88 081109 (2006).

  13. "Effects of annealing atmosphere on the luminescent efficiency of ZnTe:O phosphors,"
    Z. T. Kang, H. Menkara, B. K. Wagner, C. J. Summers, R. Durst, Y. Diawara, G. Mednikova, T. Thorson, J. Lumin. 117, 156-162 (2006).