Highly efficient linearly polarized LED via surface plasmon integrated with Ag nanocone metasurface

Abstract

Linearly polarized LEDs (LP-LEDs) hold significant potential for a wide range of advanced optoelectronic applications. Recent approaches employing single metallic gratings, with the double function of surface plasmon–quantum well (SP–QW) coupling and polarization selection, demonstrate potential for high-performance LP-LEDs. However, challenges persist in simultaneously optimizing luminous efficiency, electrical performance, and polarization degree. Therefore, we present a GaN-based blue light-emitting diode integrated with two collaborative metasurfaces, an Ag nanocone metasurface for efficiency enhancement and an Al nanograting for polarization-selective emission. Dual-structure design with collaborative functionalities resolves the trade-off between polarization selection and SP–QW coupling, while the introduction of Ag metasurface addresses the conflict between low luminous efficiency and poor electrical performance. Thereby, the fabricated LP-LED achieves highly efficient polarized emission, with an average polarization extinction ratio (ER) of 23.2 dB within ±60°, along with a 2.5-fold enhancement in efficiency and a 1.24-fold improvement in ER relative to the conventional Ag reflector design. This integrated design offers a promising route for the realization of high-efficiency, polarization-controlled optoelectronic devices, with broad implications for secure communications, advanced display technologies, optical interconnects, and biomedical diagnostics.