Plasmonics in Nanocomposite Materials: From Theory to Application Session III
Sponsored by: TMS Structural Materials Division, TMS: Composite Materials Committee
Program Organizers: Nasrin Hooshmand, Georgia Institute of Technology; Simona Hunyadi Murph, Savannah River National Laboratory; Mahmoud Abdelwahed, The University of Texas at San Antonio
Tuesday 8:30 AM
March 16, 2021
Room: RM 45
Location: TMS2021 Virtual
Session Chair: Simona Hunyadi Murph, Savannah River National Laboratory (SRNL)
8:30 AM Keynote
Nanoplasmonics and Its Applications in Nanomedicine: Mostafa El-Sayed1; 1Georgia Institute of Technology
The field of Nanotechnology showed us how different materials provide various potential applications, including nanomedicine. In this talk, I will start with a brief introduction of my scientific life and how I came to study in the field of nanotechnology. Then I will discuss some of the properties and application of plasmonic gold nanorods in cancer treatment. Plasmonic gold nanorods (AuNRs) with a length: width ratio of 3:1 can absorb near-infrared (NIR) light and convert it to heat. If a solution containing AuNRs is injected into a cancerous tumor and exposed to NIR light, the hot solution preferentially heats the cancer cells, leading to their death. Treating cancer cells with hot AuNRs, can also stop the cancer cell migration process. This treatment can retard the ability of certain cancers to metastasize and infect other locations in the body, greatly increasing the rate of the patient's recovery.
9:15 AM Invited
Fin p-n Heterojunctions for High Brightness Light Emitting Diodes and Lasers at Sub-micron Scale: Babak Nikoobakht1; Robin Hansen2; Yuqin Zong2; Amit Agrawal2; Michael Shur3; Jerry Tersoff4; 1National Institute of Standards and Technology; 2NIST; 3Rensselaer Polytechnic Institute; 4IBM T. J. Watson Research Center
“Efficiency droop” is a decline in brightness of light emitting diodes (LEDs) as electrical current density is raised. This phenomenon has limited the performance of all commercial LEDs. It has also capped the output power of sub-micron LEDs and lasers to nanowatts. In this presentation, I will discuss a fin shape heterojunction architecture that eliminates the droop effect and results in high brightness point sources with a microwatt power range exceeding the output power of any previous electrically-driven sub-micron LED or laser pixel by 100 to 1000 times. Results will be presented on the impact of fin shape on electron-hole recombination and how it impacts the rate of non-radiative Auger recombination at extreme high current densities. Results suggest further refinement of this design is expected to enable a new generation of high brightness LED and laser pixels for macroscale and miniaturized applications.
9:45 AM Invited
Spectral Enhancement of Dye Molecules Adsorbed on Titania Prepared on Gold Nanoparticles: Hiromasa Nishikiori1; Yosuke Kageshima1; Katsuya Teshima1; 1Shinshu University
Fluorescein adsorbed on TiO2/Au/Si showed obvious IR peaks, whereas the IR absorption of the dye adsorbed on the titania film without Au was quite weak. The amount of the adsorbed dye was also assessed by UV-vis absorption spectrum of the dye dissolved into acidic aqueous solution. Since the adsorption amount of the dye on the titania was independent of the Au existence, the increased IR absorption of fluorescein/TiO2/Au/Si should originate from the surface plasmon resonance of Au. The enhanced IR absorption was preferable to monitor the slight change in the electric charge on the titania surface. A peak for the asymmetric COO- stretch was located at a lower wavenumber for the titania films UV-irradiated for a longer time such that the monoanion and dianion species exhibit peaks at 1584 and 1573 cm-1, respectively. The relative amount of the dianion clearly increased by the UV irradiation due to the surface change.
10:05 AM Invited
Engineered Plasmonic Nanoparticle Based Detection: Advanced Sensitivity and Selectivity: Nasrin Hooshmand1; 1Georgia Institute of Technology
Over the past decades, gold and silver nanoparticles and their composites have received extensive attention owing to their unique properties called “localized surface plasmon resonance (LSPR)” that enables them to absorb and reradiate photons when they are exposed to electromagnetic radiation. This property made them promising candidates for chemical and biochemical sensing. The extreme levels of sensitivity arise from the LSPR associated with the nanogap of assembled nanoparticles. Using new models of interaction between nanoparticles, we have achieved a tighter localized plasmonic field, down to 2 nanometers apart in order to overcome the conventional detection limit. We also examined the plasmonic photothermal therapy by inducing localized plasmonic heating at the nuclear region of the cells. This study has provided valuable insight into the application of nanoparticles in medicine and molecular biology.