Electrostatic mechanism of strong enhancement of light emitted by semiconductor quantum wells

Plasmonically-powered hot carrier induced modulation of light emission in a two-dimensional GaAs semiconductor quantum well

“…These plasmonic NPs when excited with a source that is resonant in energy to the plasmon frequency of one species result in hot carrier generation, but if excited with a higher energy light source off-resonant to the LSP result in carrier density modulation in the semiconductor without dissipative loss. 32 We demonstrate that the hot-carrier electron transfer due to resonant pumping of AuNPs can change the frequency of emitted light in the GaAs/AlGaAs quantum well, while the PL intensity is amplified from the image charge effect induced by the GaNPs. We also establish that the angle of incidence and excitation power of the laser influence the coupling between the plasmonic metal nanoparticles and the substrate.…”

Enhanced photoluminescence emission from anthracene-doped polyphenylsiloxane glass

“…At higher quantum efficiencies, no significant change occurs in the spontaneous emission process due to the localized plasmon-induced decay. Electrostatic-charge-induced PL enhancement also saturates at high carrier densities [16]. Thus, at the anthracene concentration of 2 × 10 −2 M, the hybrid emitter exhibited negligible enhancement at any PL emission energy, as noted in Fig.…”

“…This blue shift is a signature of an increase in the total number of carriers influencing the PL emission process due to Coulomb attraction induced by electrostatic image charges [16]. The mechanism of carrier accumulation in organic molecules due to metal NPs is different from the drift-or diffusion-induced carrier transport in the case of inorganic semiconductors [16] and needs to be investigated further. An appreciable blue shift due to AgNPs is observed for anthracene concentrations that yields a large enhancement of the PL emission.…”

“…The PPS glass matrix prepared in this work contained an adequate number of anthracene molecules in the neighborhood of AgNPs, which facilitates both electrostatic [16] and electrodynamic interactions between the AgNPs and the Frenkel excitons in anthracene molecules. These interactions along with the absorption of the incident photon by the anthracene molecule within the resonant LSP spectrum lead to a significant (∼50-fold) enhancement of the PL intensity when the anthracene molecules had an optimum concentration (1 × 10 −2 M), as observed in Fig.…”

Coupling of Deep-Ultraviolet Photons and Electrons

“…The latter effect can be obtained for a wider frequency range and can therefore be used to improve the efficiency of broadband light emitters, not limited at the LSPR wavelength. Llopis et al propose an electrostatic mechanism for carrier-metallic nanoparticle interactions, comparable in effect to plasmonic interactions [82]. Arising from the coulomb attraction of electrons and holes to their image charges in a metal produces large carrier concentrations near metallic nanoparticles.…”