Plasmonic electromagnetically induced transparency in metallic nanoparticle–quantum dot hybrid systems

Abstract

We study the variation of the energy absorption rate in a hybrid semiconductor quantum dot-metallic nanoparticle system doped in a photonic crystal. The quantum dot is taken as a three-level V-configuration system and is driven by two applied fields (probe and control). We consider that one of the excitonic resonance frequencies is near to the plasmonic resonance frequency of the metallic nanoparticle, and is driven by the probe field. The other excitonic resonance frequency is far from both the plasmonic resonance frequency and the photonic bandgap edge, and is driven by the control field. In the absence of the photonic crystal we found that the system supports three excitonic-induced transparencies in the energy absorption spectrum of the metallic nanoparticle. We show that the photonic crystal allows us to manipulate the frequencies of such excitonic-induced transparencies and the amplitude of the energy absorption rate.

Schottky junction UV photodetector based on CdS and visible photodetector based on CdS:Cu quantum dots

“…Internal photoemission which is usually described by an escape cone model is more efficient at lower wavelengths, with the free-carrier absorption expected to be proportional to λ 2 causing the responsivity to increase as wavelength increases. At long wavelengths, the free-carrier absorption is independent of the wavelength and the responsivity decreases with increasing wavelength due to the decreasing internal photoemission [6,12,13,17]. The characteristics of the photoconductive CdS quantum devices suggest that they are good candidates for optoelectronic M a n u s c r i p t switches, with the dark insulatingstate as "OFF" and the light-exposed conducting state as "ON".…”

“…In 2000 S. Datta et al demonstrated the schottky junction of Ag with CdTe, CdS, ZnO; its characteristics and PV device application [1][2][3][4][5]. M. R. Singh et al demonstrated the optical switching nano-devices of metallic nanoparticle -quantum dot hybrid system ,where the photonic crystal allows to switch the absorption of the metal particle at a given frequency range when the excitonic frequencies lie near the band edge [6]. We have fabricated Ag NCs/CdS (CdS: Cu) quantum dots schottky junction and characterized for electrical and optical properties.…”

Investigation of coherent molecular resonances in quantum dot–metallic nanoparticle systems using their spontaneous emission

“…The first term in Eq. (3) indicates in the limit in which the calculated electric field distribution is dominated by dipole modes, this factor is directly related to the photoluminescence radiative decay rate enhancement of the QD [11,18,38,45]. As a result, Γ r P enh ðω e Þ represents the enhanced radiative decay rate of excitons in je〉.…”

“…This term contains energy relaxation processes associated with diagonal elements of the density matrix and dephasing of the off-diagonal elements. Except for the contribution of FRET, this term is treated in this paper in a phenomenological way [38]. …”

“…These include enhancement and switching of second harmonic generation [23,24], transfer of dressed excitons from QDs to graphene nanodisks [25,26], and excitonic population transfer in QD-MNP systems [27]. Such a coupling also allows us to control the speed of light propagation in the medium [28], generate bistability and hysteresis [29][30][31][32][33], switch from bistability to multistability [34], induce Rabi and plasmonic field oscillations [35,21], and generate Fano-type features or plasmonic electromagnetically induced transparency [36,30,[37][38][39]. Coherent exciton-plasmon coupling can also alter four wave mixing and reverse the course of energy transfer between the QDs and MNPs allowing energy drain from the MNPs to the QDs [22,40].…”