In the pursuit of developing red, green and blue emitters, comprehension of color tunability in relation to the nanostructure properties is imperative. Hence, we present a systematic study for the fabrication of color tunable emitters based on GaN nanorods (NRs) prepared via two-step etching technique. In the essence of tunable emission wavelength, aspect ratio controlled GaN NRs were employed for the growth of core shell heterostructure of InGaN/GaN multiple quantum wells (MQWs) using MOCVD and the impact of aspect ratio regulation on the emission wavelength modulation was studied. To analyze the role of the GaN NRs aspect ratio in facilitating the tunable emission wavelength, we employed metrological as well as optical characterizations. Photoluminescence spectra results established a direct relation of the aspect ratio to the emission profile of the GaN NRs. Furthermore, power-dependent photoluminescence (PL) and cathodoluminescence (CL) studies clarified the source of the emission, providing confirmation of the active region's exclusive growth on non-polar sidewalls and the absence of polarization-induced fields. Tunneling microscope measurements revealed a direct relation of the GaN NRs aspect ratio to the emission wavelength profile. In conclusion, we studied comprehensively the impact of aspect ratio regulation for the tunable emission wavelength.

中文翻译：

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三维核壳 InGaN/GaN 异质结构，用于长宽比控制的 GaN 纳米棒上的颜色可调发射器


在开发红色、绿色和蓝色发射器的过程中，必须了解与纳米结构特性相关的颜色可调性。因此，我们提出了一项基于通过两步蚀刻技术制备的 GaN 纳米棒（NR）制造颜色可调发射器的系统研究。在可调谐发射波长的本质上，采用 MOCVD 控制纵横比控制的 GaN NR 来生长 InGaN/GaN 多量子阱 (MQW) 的核壳异质结构，并研究了纵横比调节对发射波长调制的影响。为了分析 GaN NR 纵横比在促进可调谐发射波长方面的作用，我们采用了计量和光学表征。光致发光光谱结果建立了 GaN NR 的纵横比与发射轮廓的直接关系。此外，功率相关的光致发光（PL）和阴极发光（CL）研究阐明了发射源，证实了有源区在非极性侧壁上的唯一生长以及不存在极化诱导场。隧道显微镜测量揭示了 GaN NR 的纵横比与发射波长分布的直接关系。总之，我们全面研究了纵横比调节对可调谐发射波长的影响。