Friday, May 22, 2015

SID & IEEE Student Chapters Seminar: "Improving Solar Cell Efficiency beyond Shockley-Quisser Limit by Singlet Fission—Exciton Dynamics in Rubrene and Tetracene Thin Films" by Dr. Jiun-Haw Lee 5.27.15/11:00am-12:00pm/ CREOL RM A214

SID & IEEE Student Chapters Seminar: "Improving Solar Cell Efficiency beyond Shockley-Quisser Limit by Singlet Fission—Exciton Dynamics in Rubrene and Tetracene Thin Films" by Dr. Jiun-Haw Lee
Wednesday, May 27, 2015 11:00 AM to 12:00 PM
CREOL Room A214

Celebrating the International Year of Light 2015
     

Dr. Jiun-Haw Lee
Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University

Abstract:
Exciton fission is a process to split one singlet exciton into two triplet excitons. By dissociating those two excitons into carriers, it is possible to generate super high internal quantum efficiency (> 100%, ideally 200%). In our experiments, transient photoluminescence (TRPL) was used to study exciton fission and fusion dynamics characteristics. Fusion rate increased with decreasing the film thickness, which was due to the triplet exciton confinement. Excitons were quenched by Si substrate which showed the possible energy transfer process between organic material and Si.

Biography:
Dr. Jiun-Haw Lee received the B.S.E.E., M.S.E.E., and Ph.D. degrees in electrical engineering in 1994, 1995, and 2000, respectively, all from National Taiwan University, Taipei, Taiwan.From 2000 to 2003, he was with the RiTdisplay Corporation as the director. Since 2003, he joined the faculty of National Taiwan University in the Graduate Institute of Photonics and Optoelectronics and the Department of Electrical Engineering, where he is currently a professor. His research interests include organic optoelectronic devices, display and lighting technologies, and solar cells.He has co-authored over 80journal papers, over 250conference papers, and 50 patents.

For more information:
SID UCF Student Branch Chair: Fenglin (Maple) Peng
SID UCF Student chapter advisor: Prof. Shin-Tson Wu
IEEE Photonics Society Chair: Ruidong Zhu

Thursday, May 21, 2015

TOMORROW! Seminar: "What can we learn in glass materials combining conventional infrared and Raman with unconventional hyper-Raman and hyper-Rayleigh techniques?" By Dr. Vincent Rodriguez 5.22.15/3:00-4:00pm/ CREOL RM 103

Seminar: "What can we learn in glass materials combining conventional infrared and Raman with unconventional hyper-Raman and hyper-Rayleigh techniques?" By Dr. Vincent Rodriguez
Friday, May 22, 2015 3:00 PM to 4:00 PM
CREOL Room 103

Celebrating the International Year of Light 2015

Vincent Rodriguez 
Institute of Molecular Science (ISM), University of Bordeaux, Talence, France.

Abstract:
Vibrational spectroscopies are suitable techniques to get structural and dynamical insights from a wide range of systems at the molecular scale. The combination of spontaneous hyper-Raman scattering (HRS), which is a nonlinear vibrational technique, to other conventional vibrational techniques as infrared (IR) and Raman scattering (RS) has enriched this field.  Harmonic light scattering (HLS), also called hyper-Rayleigh scattering, provides unique additional information about the nature and structure/symmetry of the scatterers.

Biography:
Prof. Vincent Rodriguez obtained his PhD in Physical Chemistry in 1989 at the University of Bordeaux (France). After a postdoc at the University of Geneva (Switzerland) and at the “Institut Laue-Langevin” (European Neutron Research Facilities) in Grenoble (France), he returned in 1993 to the University of Bordeaux as assistant professor. He obtained the “Habilitation à diriger les recherches” (HDR) at the University of Bordeaux in 2003. Since 2007 he is a full professor of Physical Chemistry at the University of Bordeaux. Over the years, he has contributed in the field of vibrational spectroscopies as well as nonlinear optics techniques like second Harmonic Generation, hyper-Raleigh Scattering, hyper-Raman Scattering. His recent areas of interest concern novel photonic materials for nonlinear optics applications and imaging, molecular switches and molecular and supramolecular chirality. He has co-authored more than 140 peer-reviewed papers including review papers, one book and three book chapters, covering the fields of material chemistry and nonlinear optics. 

For additional information:
Dr. Kathleen A. Richardson

407-823-6815

Wednesday, May 20, 2015

Orlando optics company wins the Cade Prize for innovation



The company was selected to win the $50,000 prize over 84 other young Florida companies for the innovation and market potential of its technology



Orlando, Fla., May 20, 2015 -- EVERIX, a design and manufacturing firm for high-performance interference optical filters, today announced that it has won the 2015 Annual Cade Museum Prize. The Cade Museum for Creativity and Invention's annual competition is for early-stage inventors and entrepreneurs in Florida with ideas that demonstrate innovation, large potential impact in the world, and market credibility. EVERIX was selected the winner after the four finalists gave presentations to the audience at the inaugural Inventivity Bash and a panel of judges reviewed the inventions and business plans vying for the $50,000 award.

The Community Foundation of North Central Florida provided the cash award, while the Florida-based law firm of Lowndes, Drosdick, Doster, Kantor & Reed, P.A. offered $10,000 in in-kind legal services.

"Winning this serious cash prize could enable us to achieve some of our key business milestones at a faster pace, but even more valuable to us were the comments and feedback from the Cade Museum’s seasoned panel of judges" said E. Hooman Banaei, the Founder and CEO of EVERIX. "The judges were among the best, a great mix of business leaders and technologists. Winning this tight competition gave us the confidence that our company is on track with a game-changing technology," he added.

EVERIX recently launched its unique flexible ultra-thin optical filters with scratch-insensitive performance and easy custom-shaping for OEM customers requiring volume consistency across a multitude of industries. The company has already received inquiries from several industries, including medical imaging for early cancer detection, defense and safety equipment manufacturers.

About EVERIX

EVERIX specializes in custom design and manufacturing of high-performance interference optical filters with hundreds to thousands of nano-layers for high wavelength selectivity and spectrum customization. The company's proprietary technology for non-deposition fabrication of simple to complex interference optical filters with both rigid and flexible substrates enables consistent volume production beyond conventional possibilities. EVERIX’s new manufacturing approach lifts some key limits the optical coating industry has had even after four decades of maturity. EVERIX provides advantageous alternatives for many existing markets and enables several new markets previously prohibitive due to the coating technology limits. www.everix.co

About Cade Museum for Creativity and Invention

The Cade Museum for Creativity and Invention offers classes, programs, and exhibits that are designed to engage visitors in "purposeful creativity," the kind that leads to great inventions, new businesses and ideas that change the world. The Cade Museum Prize is an annual competition for early-stage inventors and entrepreneurs in Florida. The goals of the $50,000 prize are to provide seed capital and publicity for great ideas with market potential.


Contact:
E. Hooman Banaei, PhD
Found and CEO, EVERIX, Inc.
+1(407) 637-2987

Media Contact:
Nadia Ballard
Market Growth Strategies LLC
+1(407) 716-8435

Thursday, May 14, 2015

Sensing/Imaging Faculty Candidate Seminar: "Thin-film Materials for Next-Generation Optoelectronics" by Dr. Kyle Renshaw 5.26.15/11:00am-12:00pm/ CREOL RM 103

Sensing/Imaging Faculty Candidate Seminar: "Thin-film Materials for Next-Generation Optoelectronics" by Dr. Kyle Renshaw
Tuesday, May 26, 2015 11:00 AM to 12:00 PM
CREOL Room 103

Celebrating the International Year of Light 2015

Dr. Kyle Renshaw

Abstract:
The conventional semiconductors that enable modern optoelectronics are limited in their applications due to their specific set of materials properties. The next generation of devices will be based on thin-film optoelectronic materials such as organic molecules, metal-oxides, graphene, and thin-films of conventional inorganic semiconductors. Thin-film materials offer new optical, electrical and mechanical properties that can be used develop devices with radically different architectures and functionality. Over the last three decades, these materials have been developed to enable inexpensive, large area, non-planar, flexible and/or transparent devices. This first consumer application of these materials recently arrived as large area organic LED displays in cell phones and televisions.
This talk will introduce basic properties of some archetypal thin-film materials and will highlight why these materials are well-suited for the next generation of optoelectronic devices. We will discuss the physical processes involved in photodetection and solar energy harvesting using these materials; next we identify the primary challenges that must be overcome to realize high-performance devices. Examples of broadband sensors, novel imagers and organic photovoltaics will be provided.

Biography:
Since 2013, Dr. Kyle Renshaw has been a physicist in the Advanced Technology Center of the Electronic Systems division of Northrop Grumman Corp. located in Rolling Meadows, IL. He is an optoelectronics specialist with interest and experience in: 1) photodetection from the ultraviolet to the long-wave infrared, 2) image system characterization and modelling, 3) image processing and tracking, 4) novel semiconductor fabrication techniques, and 5) thin-film device design, fabrication, characterization and modelling. He received a B.S. in Engineering Physics from Cornell University in 2007. His M.S. in Electrical Engineering was conferred in 2012 and Ph.D. in Applied Physics was conferred in 2014 - both from the University of Michigan.

For additional information:
Dr. Demetrios Christodoulides

407-882-0074

TOMORROW! Seminar: "Structure, Optical Properties, and Crystallization in Multicomponent Chalcogenide Glasses" by John McCloy 5.15.15/3:00-4:00pm/ CREOL RM 103

Seminar: "Structure, Optical Properties, and Crystallization in Multicomponent Chalcogenide Glasses" by John McCloy
Friday, May 15, 2015 3:00 PM to 4:00 PM
CREOL Room 103

Celebrating the International Year of Light 2015

John McCloy

Abstract: 
The search for producible materials with simultaneous occurrence of superior thermo-mechanical properties and long-wave infrared (LWIR) transmission has been a longstanding problem in infrared ceramics engineering.  Recent research has suggested the possibility of using chalcogenide glass processing as a means to achieve breakthroughs in this area.  This talk will focus on three aspects of this problem.  1) vision and scoping experiments for fully ceramized LWIR glass ceramics based on sulfide glasses; 2) prediction methods of optical properties of multicomponent IR glasses; and 3) comparative topological effects on structural and optical properties of ternary Ge-based chalcogenide glasses. 

Long-wave Infrared Transmitting Glass-Ceramics
Three sulfide systems were explored including two with La2S3 in hopes of imparting strong bonds from this refractory sulfide, and two containing GeS2 in hopes of widening the glass-forming region. Attempts were made to produce glasses in the Ga2S3-La2S3-(ZnS,CaS) system, the GeS2-La2S3 system, and the GeS2-Ga2S3-CdS system. Microstructural and thermal analyses were used to explore nucleation and growth in these systems and infrared transmission and mechanical hardness showed potential for LWIR window use. The GeS2-Ga2S3-CdS system showed good LWIR transmission and pre-crystallized hardness superior to chemical vapor deposited ZnS. The Ga2S3-La2S3 glasses did not appear to be viable candidates at this time due to strong tendency for phase separation, a small temperature window between crystallization and glass transition temperatures, and problems with oxygen contamination in the La2S3 source. Glass formation in these materials is shown to be a strong function of quenching method and raw materials.  Suggestions are made for alternative methods for producing fully ceramized LWIR-transmitting glass ceramics. 
Optical Property Prediction in Infrared Glasses
It is often useful to obtain custom glasses that meet particular requirements of refractive index and dispersion for high-end optical design and applications.  In the case of infrared glasses, limited experimental data are available due to difficulties in processing of these glasses and also measuring refractive indices accurately.  Methods for estimating refractive index and dispersion as a function of composition for selected infrared-transmitting glasses are reviewed and evaluated, including Gladstone-Dale, Wemple-DiDomenico single oscillator, Optical basicity, and Lorentz-Lorenz total polarizability.  Various estimates for a set of PbO-Bi2O3-Ga2O3 (heavy metal oxide) and As-S (chalcogenide) glasses are compared with measured values of index and dispersion.  Problems associated with known glass topology changes and index prediction are discussed.      
Topological Effects on Properties of Ge-based Ternary Chalcogenide Glasses
Germanium based ternary chalcogenide glasses have been explored for over 50 years.  However, glass scientists are still discovering the complexities of these systems, particularly in relation to the continuum between random covalent network (RCN) and chemical ordered covalent network (COCN) structures. Recent understanding of crystal precipitation in these glass systems has aided in understanding of the medium range ordering.  In this final part of the talk, a comparison is made between the behavior of glass transition versus average coordination number for known compositions in Ge-Ga-Se, Ge-Ga-S, Ge-Sb-Se, and Ge-As-Se systems.

Biography:
John McCloy, PhD, is an Associate Professor of Materials Science and Engineering at Washington State University (WSU) in the School of Mechanical and Materials Engineering
(MME). He hold degrees in Materials Science & Engineering from the Massachusetts Institute of Technology and the University of Arizona. From 2008-2013 he was a senior scientist at the Pacific Northwest National Laboratory (PNNL), for the last several years as Team Lead of Glass and Materials Science. From 2000-2008 he was with Raytheon Missile Systems working on infrared systems and materials. Dr. McCloy has held roles in line management, technology management, research and development, engineering, and manufacturing. He has worked in operations, test, and engineering organizations, and led multi-disciplinary project teams of >20 in both manufacturing and engineering research & development. His current research and teaching at WSU involves Nuclear, Optical, Magnetic, and Electronic materials, with particular focus on the effect of disordering on structure and functional properties.

For additional information:
Dr. Kathleen Richardson

407-823-6815

TOMORROW! Seminar: "Tailoring crystallization in oxide glasses: Application to transparent polycrystalline ceramics and nanostructured glass-ceramics" by: Mathieu Allix 5.15.15/11:00am-12:00pm/ CREOL RM 103

Seminar: "Tailoring crystallization in oxide glasses: Application to transparent polycrystalline ceramics and nanostructured glass-ceramics" by: Mathieu Allix
Friday, May 15, 2015 11:00 AM to 12:00 PM
CREOL Room 103

Celebrating the International Year of Light 2015

Abstract: 
Crystallization from glass can be a powerful process to elaborate innovating transparent materials for optical and photonic applications if nucleation and crystal growth steps can be precisely controlled. This talk will focus on two main applications: transparent polycrystalline ceramics elaborated by full and congruent crystallization from glass and nanostructured glass-ceramics designed from nanoscale phase separated glasses.
Transparent polycrystalline ceramics elaborated by full crystallization from glass
Transparent polycrystalline ceramics are an emerging class of photonic quality materials competing with single crystal technology for a diverse range of applications including high-energy lasers, scintillating devices, optical lenses, and transparent armor. Polycrystalline ceramics offer several advantages, particularly in the fabrication of complex shapes and large-scale industrial production, and enable greater and more homogenous doping of optically active ions than is possible in single crystals. However, up to date, only a limited number of such materials has been reported. These are either cubic or nanocrystalline transparent polycrystalline ceramics which require complex, time-consuming and so expensive synthetic approaches.
Our recent work shows the possibility to obtain transparent polycrystalline ceramics by full and congruent crystallization from glass. Transparency is observed despite micrometer scale crystals and a non cubic symmetry (no structural isotropy) of the crystalline phase. Interestingly, crystallization from glass can give access to new crystalline phases given the relatively low crystallization temperature compared to classic solid state elaboration temperature. This is demonstrated in the case of a new composition, BaAl4O7, showing the existence of two orthorhombic polymorphs both showing high transparency in the visible and infra-red ranges [1,2]. The crystallographic structures of these polymorphs have been determined ab initio from powder diffraction data. From these structural models, the optical birefringence has been obtained by DFT calculations of the dielectric function. These results enable to discuss the transparency property of these materials as a function of the determined crystalline structures and the observed microstructures. Remarkably, these materials show promising scintillation properties when doped by europium [3]. The same elaboration process has been applied to cubic compositions, Sr3Al2O6 and Sr3Ga2O6, allowing very high transparencies to be attained [4]. Lastly, we have focused our work on strontium aluminosilicate compositions, the addition of silica enabling large scale glass samples to be obtained. The full and congruent crystallization of Sr1+x/2Al2+xSi2-xO8 compositions leads to new transparent polycrystalline ceramics forming a crystalline solid solution exhibiting hexagonal symmetry. These materials show an impressive transmittance higher than 90%, which sets a transparency record for oxide ceramics. A crystallographic study coupled to NMR experiments and DFT calculations of the birefringence allowed us to evidence the role of structural disorder (Al/Si substitution and presence of vacancies on strontium sites) in the origin of the optical isotropy observed in these structurally anisotropic materials. These results propose an innovative concept, the addition of a controlled structural disorder within crystalline structures, in order to lower the birefringence and to elaborate new transparent ceramics [5].

New nanostructured gallogermanate- and gallosilicate-based glass materials exhibiting high transparency in the visible range have been fabricated by conventional melt-quenching. These materials can accommodate wide oxide compositions and present nanoscale phase separation. The size of the nanostructuring can be tailored depending on the nominal composition. A single heat treatment then allows selective crystallization of the phase separated glass, resulting in glass-ceramic materials exhibiting nanostructures and transparency similar to the parent glass.[6,7]
The wide possibilities of designing new nanostructured glass-ceramics with tunable optical properties will be illustrated in the case of a highly transparent ZnGa2O4 glass-ceramic exhibiting 50 wt% of nanocrystals with homogeneous and tunable sizes. High resolution scanning transmission electron microscopy analysis coupled with in situ high temperature X-ray diffraction and optical measurements led to a detailed description of the crystallization process. Remarkably, red long-lasting luminescence arising from the entire sample volume is observed in this Cr3+ doped material, opening the route to a wider range of performing applications for this famous zinc gallate persistent phosphor.[8,9]

1. M.Allix, S.Alahrache, F.Fayon, M.Suchomel, F.Porcher, T.Cardinal, G.Matzen, Highly Transparent BaAl4O7 Polycrystalline Ceramic Obtained by Full Crystallization from GlassAdvanced Materials, 24 5570-5575 (2012)
2. "Transparent aluminate glass, glass-ceramics and ceramics", International patent deposited 1/12/2011, published 6/6/2013, WO2013079707 A1, PCT international extension PCT/EP2012/074171, US20140336032 13/11/2014.
3. G.Patton, F.Moretti, A.Belsky, K.Al Saghir, S.Chenu, G.Matzen, M.Allix, and C.Dujardin, Light yield sensitization by X-ray irradiation in BaAl4O7 : Eu2+ ceramic scintillator obtained by full crystallization from glassPhysical Chemistry Chemical Physics., 16 24824 (2014)
4. S.Alahraché, K.Al Saghir, S.Chenu, E.Véron, D.De Sousa Meneses, A.I.Becerro, M.Ocaña, F.Moretti, G.Patton, C.Dujardin, F.Cussó, J-P.Guin, M.Nivard, J-C.Sangleboeuf, G.Matzen, M.Allix, Perfectly transparent Sr3Al2O6 polycristalline ceramic elaborated from glass crystallizationChemistry of Materials, 25 4017-4024 (2013)
5. K.Al Saghir, S.Chenu, E.Veron, F.Fayon*, M.Suchomel, C.Genevois, F.Porcher, G.Matzen, D.Massiot and M.Allix*, Transparency through Structural Disorder: A New Concept for Innovative Transparent CeramicsChemistry of Materials, 27 508-514 (2015)
6. "Nanostructured glass and glass-ceramics transparent in the visible and infrared ranges"International patent deposited 28/02/2014, published 4/9/2014, WO2014131881 A1, PCT in progress, PCT/EP2014/053932.
7. S.Chenu, E.Véron, C.Genevois, G.Matzen, T.Cardinal, A.Etienne, D.Massiot, M.Allix, Tuneable Nanostructuring of Highly Transparent Zinc Gallogermanate Glasses and Glass-CeramicsAdvanced Optical Materials, 2 364 (2014)
8. S. Chenu, E. Veron, C. Genevois, A. Garcia, G. Matzen, M. Allix, Long-lasting luminescent ZnGa2O4:Cr3+ transparent glass-ceramics,Journal of Materials Chemistry C, 2 10002-10010 (2014)
9. M.Allix, S.Chenu, E.Véron, T.Poumeyrol, E.A.Kouadri-Boudjelthia, S.Alahraché, F.Porcher, D.Massiot, F.Fayon, Considerable improvement of long-persistent luminescence in germanium and tin substituted ZnGa2O4Chemistry of Materials, 25 1600–1606 (2013)
Keywords: Glass crystallization, transparent polycrystalline ceramics, transparent glass-ceramics, phase separation, structure determination from powder diffraction, long lasting luminescence, scintillation, Transmission electron

Biography:
Dr. Mathieu Allix is a CNRS researcher in material chemistry in Orléans, France. He received his PhD from the University of Caen in 2004 and eventually moved to a 3 years postdoctoral position in Liverpool, UK under the supervision of Matt Rosseinsky. His research focuses on crystallization in oxide glasses with an application to transparent polycrystalline ceramics elaborated by full and congruent crystallization from glass and nanostructured glass-ceramics designed from nanoscale phase separated glasses. He is author of over 70 publications and recently received the CNRS bronze medal award.

For additional information:

Dr. Kathleen Richardson

Tuesday, May 12, 2015

Seminar-“New Magnetic Resonance Approaches Towards the Structural Characterization of Luminescent Ceramic Materials” by Hellmut Eckert/5/12/15, Noon-1pm/CREOL 103

“New Magnetic Resonance Approaches Towards the Structural Characterization of Luminescent Ceramic Materials”
Tuesday, May 12, 2015/12:00-1:00pm
CREOL RM 103
                                                                                                                   

Hellmut Eckert
1 Instituto de Física Sao Carlos, Universidade de Sao Paulo, Brazil
2Institut für Physikalische Chemie, WWU Münster, Germany

Celebrating the International Year of Light 2015


Abstract:
Rare-earth doped glasses and vitroceramics have been introduced as excellent alternatives to single crystalline host materials for luminescent rare-earth ions with special laser applications To optimize the luminescent properties of these materials, detailed structural information regarding the local environment of the rare-earth species in the glassy state is essential. This characterization must include the distribution of the rare earth ions in space and over the different crystalline and amorphous components present. While solid state nuclear magnetic resonance (NMR) is in general a promising tool for such purposes, unfortunately, the rare-earth ions themselves cannot be studied by NMR due to their paramagnetism. To overcome this difficulty, we have developed a comprehensive examination strategy consisting of (a) the use of diamagnetic mimics (45Sc and 89Y NMR), (b) the quantification of paramagnetic broadening effects imparted by the rare-earth ions upon the solid state NMR spectra of framework atoms, and (c) the direct study of electron-nuclear interactions as probed by electron spin echo envelope modulation (ESEEM) spectroscopy. Results will be presented for a range of rare-earth containing fluorophosphates, aluminophosphate, and aluminoborate, glasses and ceramics, and extensions to other laser ceramic systems will be discussed.




Biography:
Hellmut Eckert
Professor of Physical Chemistry at the Westfälische
Wilhelms-Universität, Münster, Germany and
Institute of Physics, University of São Paulo, São Carlos.
              
1973 - 1978         Studies of Chemistry, WWU Münster
1982      PhD (Dr. rer. nat.), WWU Münster
1982 - 1984         Postdoctoral fellow, Rutgers University, New Brunswick,USA
1984-1987           Staff Scientist, California Institute of Technology, Pasadena, USA
1987-96               Assistant, Associate, and Full Professor, Analyt. Chemistry, UC Santa Barbara, USA
since 1995           Universitätsprofessor  Physical Chemistry, C4, WWU Münster, Germany
since 2011           Professor Titular, Physics, Universidade São Paulo, São Carlos, Brazil.

Editor, Chemistry of Materials (1998-2011), Editor, Solid State Nuclear Magnetic Resonance (since 1991), Member, Scientific Advisory Board, Alexander-von Humboldt Foundation, Germany (since 2010), ~440 publications, ~ 9500 citations, h-Index 44, CNPq: 1A,


For additional information:
Dr. Leonid B. Glebov

407-823-6983