Electroluminescence and temperature-dependent time-resolved photoluminescence of monolithically integrated triple-wavelength InGaN-based LED

Abstract

Here, we propose a monolithically integrated triple-wavelength InGaN-based LED structure and conduct comprehensive research on its emission dynamics under electrical and optical excitation. Through experimental and numerical analyses, a carrier transport and a recombination process can be manipulated in bandgap-engineered multiple quantum wells (MQWs), thus realizing the manipulation of emission properties. A rational triple-wavelength LED structure is heteroepitaxially grown, which shows excellent color stability versus injected currents. Furthermore, utilizing the temperature-dependent time-resolved photoluminescence (TRPL), triple-wavelength peaks display different TRPL decay behaviors. Especially, an anomalous three-stage decay phenomenon is found for a low-energy peak measured at 10 K, accompanied by a decay profile transition with the increasing temperature. The underlying mechanisms are revealed and correlated with carrier localization, interaction between different QWs, and competition between radiative and nonradiative recombination.