Optical properties of light emitting diodes with a cascading plasmonic grating

Abstract

In this paper, the polarization dependent optical properties of InGaN/GaN multi-quantum wells (MQWs) LED with cascading plasmonic gratings are investigated using an angle-resolved photoluminescence (ARPL) spectrometer. The plasmonic gratings consist of two Ag gratings with a half-pitch displacement. The ARPL spectra of the TE-TM state present a broadband emission with resonance dips occasioned by the SP resonance while the TM-TE state presents resonance peaks with low sideband emission. The resonance properties can be tuned by modifying the geometric parameters of the plasmonic grating. The ARPL spectrum of the LED sample with pure GaN 1D grating is also measured and discussed. The investigated plasmonics LED represents resonance optical properties different from the conventional surface relief LED, which can be used in special applications.

Polarization-Independent Light Emission Enhancement of ZnO/Ag Nanograting via Surface Plasmon Polariton Excitation and Cavity Resonance

“…It should be noted that the semiconductor/metal grating structures show angle-dependent PL spectra determined by the dispersion relations of SPP and guided modes. 16,17 Therefore, such directional and enhanced emission properties can be optimized for specific intended applications.…”

“…18,19 ZnO is a key material in various applications due to its wide band gap energy, large refractive index, and material compatibility. Thus, the application of ZnO includes photodetectors, 10 fluorescent biosensors, 14,15 light-emitting diodes, 16,17 and back reflectors for thin-film solar cells. 18,19 In all these studies, the plasmonic effects in the ZnO/metal structures play major roles in improvement of the device performance.…”

“…Additionally, metallic gratings can exhibit anomalous reflection spectra, due to excitation of surface plasmon polariton (SPP). − SPPs originate from the oscillatory motion of free carriers in metals, and generate propagating electromagnetic fields concentrated at the metal–dielectric interface. SPPs have a larger momentum than photons with identical energy; hence, coupling with the radiative electromagnetic field is possible with the help of the reciprocal lattice vector from periodic structures (i.e., gratings). − SPPs are associated with fascinating physical phenomena, including extraordinary optical transmission , and enhanced light absorption/emission. − Thus, extensive research has been devoted to understanding the nature of SPPs and the fabrication of novel periodic nanostructures for exploiting the beneficial roles of SPPs.…”

Optical properties of InGaN/GaN multiquantum wells light-emitting diode with one-dimensional Au nanoparticle grating

“…31 The SP propagating along the interface is accompanied with heat dissipation, i.e., nonradiative loss, which leads to the dark fringe. 31 The SP propagating along the interface is accompanied with heat dissipation, i.e., nonradiative loss, which leads to the dark fringe.…”

Exploiting plasmonics in active photonic devices

“…(a) The angle-resolved photoluminescence spectra of indium gallium nitride (InGaN)/GaN multiple-quantum-well LEDs with a plasmonic grating of period 0.3 m shows a clear resonance peak redshift from 453.3 to 456.8nm as the collecting angle increases from 35 to 37 ı in transverse magnetic-transverse electric (TM-TE) mode. (b) In TE-TM mode a dark fringe is observed for incident angles  D 21 ı to  D 30 ı for emission at a wavelength of 430 to 470nm.The dashed line shows the theoretical grating-coupled surface-plasmon dispersion relation of the Ag/GaN interface 5. …”