Prof. Arup Neogi(Department of Physics and Electrical Engineering, University of North Texas)をお招きして下記日程にて第7回サイエンスカフェ講演会を開催するはこびとなりました．

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日時：8月6日14:00～15:30頃
場所：T1－8F　サイエンスカフェ

講演者：Prof. Arup Neogi(Department of Physics and Electrical Engineering, University of North Texas)

題目：Moving Nanophotonics Beyond Plasmonics for efficient light emission and coherent interaction

概要：
Plasmonics has been identified as the next generation technology for
coherent interaction and nanoscale photonic devices such as light
emitters and detectors. It has been shown that coupling to surface
plasmons can produce an enhancement in photoluminescence intensity as
well as strongly confined light emission. Surface plasmon enhanced light
emission or detection, however, is limited by strong dissipative effects
as well as strict energy and momentum matching conditions for resonant
interaction with the emitter or absorber. This combination of loss due
to dissipation and the narrow window for resonant interaction with the
plasmons limits the overall efficiency of devices and requires careful
tailoring of the system.
Instead of the electrodynamically-induced modification of the radiative
recombination rate produced via plasmonics, we present an alternative
mechanism for increasing the internal quantum efficiency of a light
emitter based on carrier concentration modulation via electrostatic
interaction with embedded metallic nanoparticles. This universal
electrostatic effect is not dissipative and lacks the stringent
frequency and energy matching imposed on surface plasmon coupling.  We
present light enhanced from Au nanoparticles embedded in epitaxially
(MOCVD) grown InGaN/GaN multiple quantum wells, Au nanoparticles
embedded in ion-implanted Si/ SiO2 nanocrystals, and metallic Ga
nanoparticles on the surface of an MBE grown AlGaAs/GaAs quantum well.
We also propose a novel mechanism of modifying coherent acoustic phonon
generation using metal nanoparticles. The zone folded acoustic phonon
oscillation in InGaN/GaN superlattice can be modified due to coherence
induced by the metal nanoparticles.