Influence of the quantum-confined Stark effect in an InGaNGaN quantum well on its coupling with surface plasmon for light emission enhancement
Journal
Applied Physics Letters
Journal Volume
90
Journal Issue
18
Date Issued
2007
Author(s)
Abstract
The authors analyze the contribution of the screening of the quantum-confined Stark effect (QCSE) to the emission enhancement behavior in the process of surface plasmon (SP) coupling with an InGaN∕GaN quantum well (QW), which is 20nm away from a Ag thin film that supports the SP. From the measurements of excitation power dependent photoluminescence and time-resolved photoluminescence (TRPL) spectroscopy, and the fitting to the TRPL data based on a rate-equation model, it is found that when the excitation level is high, the QCSE screening effect not only contributes significantly to the emission enhancement but also increases the SP coupling rate because of the blueshift of emission spectrum caused by the screening effect. Therefore, the emission strength from SP radiation, relative to that from QW radiative recombination, increases with the excited carrier density. Also, a saturation behavior of SP-QW coupling is observed from the fitting procedure.
SDGs
Type
journal article