Numerical study of polarization-dependent emission properties of localized-surface-plasmon-coupled light emitting diodes with Ag/SiO2 nanoparticles

Abstract

We study polarization-dependent spontaneous emission (SE) rate and light extraction efficiency (LEE) in localized-surface-plasmon (LSP)-coupled light emitting diodes (LEDs). The closely packed seven Ag/SiO2 core-shell (CS) nanoparticles (NPs) lie on top of the GaN surface for LSP coupling with a radiated dipole. According to the dipole direction, both the SE rate and the LEE are significantly modified by the LSP effect at the Ag/SiO2 CS NPs when the size of Ag, the thickness of SiO2, and the position of the dipole source are varied. The enhancement of the SE rate is related to an induced dipole effect at the Ag, and the high LEE is caused by light scattering with an LSP mode at Ag/SiO2 CS NPs. We suggest the optimum position of the quantum well (QW) in blue InGaN/GaN LEDs with Ag/SiO2 CS NPs for practical application.