• A figure from our published paper has been chosen to appear on cover 1 of the 14 August 2017 issue of Journal of Applied Physics. This paper was with the collaboration of Nanophotonics and Quantum Devices Group at The University of Alabama in Huntsville. “Optically saturated and unsaturated collective resonances of flat metallic nanoantenna arrays”, Journal of Applied Physics,122, 063102 (2017).

  • SPIE Nanoscience + Engineering  9 August 2017 –  San Diego, California United States
    Title: “Tunable coupling between exciton-polariton and exciton-surface plasmon in hybrid systems consisting of VO2 nanoparticles and quantum dots”

Abstract: Vanadium dioxide (VO2) features a semiconductor to metal phase change characteristic that leads to an abrupt change in the particle’s optical properties. A hybrid system consisting of semiconductor quantum dot (SQD) and vanadium dioxide nanoparticle (VO2NP) can support the coherent coupling of exciton-polaritons and exciton-plasmon polaritons in the semiconductor and metal phases of the VO2NP, respectively. In this talk, we theoretically show that the controlling over the VO2NP phase change transition alters the SQD optical response drastically in comparison to a bare SQD. The results can be applied to the design of thermal sensors at the nanoscale.

  • Math Talk Series – 28 May, 2017 – 1:15pm to 2:30pm in room A129.Title: “Quantum Dot Nanophotonics”

Abstract:  Quantum dots (QDs), known as artificial atoms, are nanoscale semiconductor materials with a unique size-tunable optical property. These unique size dependent qualities lead to a narrow photoluminescence spectrum in the range of visible to infrared light. QDs have attracted tremendous attention in the past few years for a variety of scientific and commercial applications such as biological sensors, quantum commuting, photovoltaic and light emitting devices. In this talk we present a brief description of QDs and their associated optical properties,highlighting the concept the size dependent photo-physical properties. We also show how the coupling of QDs with the other nanostructures can dramatically alter the QDs photoluminescence for further development of QDs for each respective application.

  • 4th Conference of Engineering and Physics of Plasma, Yazd, Iran, 18 – 20 May, 2016 (Plenary Speaker)Title: “Plasma mediated Response from Plasmonic Nanostructures Irradiated by Ultrafast Laser for Biomedical Application”
  • Photonic West, San Francisco, CA, United States, 13 – 18 February, 2016
    Title: “Analysis of Photoacoustic Response from Plasmonic Nanostructures Irradiated by Ultrafast Laser in Water”
    Abstract:  Gold and silver plasmonic nanoparticles (NPs) are widely used as a contrast agent for photoacoustic (PA) imaging, taking advantage of the strong optical absorption cross-section of these particles due to their localized surface-plasmon resonance. Inspired by recent developments in ultra-high frequency wide-bandwidth transducers, we propose utilizing off-resonance ultrashort laser sources with a pulse width in the femtosecond (fs) and picosecond (ps) range to increase the efficiency of PA imaging. Also, from the fact that the laser pulse duration is shorter than the heat diffusion time of the materials, we expect practically no collateral damage of the laser irradiated biological tissues. Our preliminary studies show that irradiating the NPs with an ultrashort-pulsed laser has the potential to achieve substantially higher efficiency at generating the PA signal. Enhanced by the presence of NPs, the laser field causes a highly localized plasma nucleation around the vicinity of the NPs. Plasma relaxes through electron-ion interaction and releases a pressure wave in the surrounding medium. However, in this process, it is crucial to precisely control the heat energy absorption in the NPs to avoid their fragmentation. In this talk we present a model to simulate an optimized plasma–mediated PA signal dynamics generated from off-resonance ultrashort laser excitation (λ =800 nm, τ = 70 fs – 2 ps) of a variety of plasmonic NPs with sizes ranging from 50 nm to 100 nm.
  • Computer Science, Mathematics, and Physics Lectures (1:00 PM – Oct. 17, 2015 – Room A251)
    Title: “Fundamentals and Design of Nanostructures for Nanomedecine Applications”
    Abstract: In the past decades intensive research and development have been devoted to bring basic science, engineering, biology and medicine together to obtain innovative approaches and solutions to current health problems. Nanomedicine, the application of nanotechnology that deals with its applications to the medical world, is one of the most noteworthy examples of this convergence. This talk deals with the applications of optics to nanomedecine, mostly emphasising the physics and engineering developments.
  • Dept of Computer Science & Mathematics Seminar – Friday, Nov 14, 10:00am
    Title: “Fundamentals of Plasmonics and Design of Metallic Nanostructures for Plasmon-Enhanced Applications”
    Abstract: Light interaction with plasmonic (metallic) nanostructures opens up new and interesting physical phenomena on the nanoscale.  Recent experimental evidence suggests that these nanostructures can be utilized in a broad range of applications including solar energy harvesting, sensing, and biomedical applications; however, the development of theoretical models based on fundamental physics is absolutely necessary in order to guide the rapid development of these nanostructures for broader use.  In this introductory presentation I will speak about some of the current research projects in the area of plasmon-assisted nanophotonics being carried out in the newly established Computational Physics Lab in the Department of Computer Science and Mathematics at Nipissing.
  • Physics Day (March 6th, 2015)
    The Math and Computer Science department is pleased to announce that we have organized Physics Day that is scheduled for Friday, March 6th. Here is the attempt schedule for Physics Day.
    9:30 – 9:45                Welcome to Nipissing
    9:45 – 10:30              Research Presentation (Ali Hatef)
    10:30 – 11:30            Class/Lab Activities
    11:30 – 12:15            Lunch (Pizza)
    12:15 – 1:15              Class/Lab Activities
    1:15 – 2:15                Presentation (Carmen Wehrstedt)
    2:15 – 2:30                Prizes and Good Bye!