Current Science Research Bulletin

Light-emitting diodes (LEDs) have revolutionized modern lighting and optoelectronic technologies owing to their high energy efficiency, long operational lifetime, and versatile applications. This review provides an overview of the historical development of LED technology, from the discovery of electroluminescence to the emergence of high-efficiency blue and white LEDs and advanced Micro-LED systems. The fundamental physical principles of light emission, semiconductor materials, and technological advances are discussed, with particular emphasis on GaN-based heterostructures and quantum-well engineering. Major applications in solid-state lighting, display technologies, optical communications, agriculture, and biomedical systems are highlighted. Furthermore, current challenges related to quantum efficiency, material defects, thermal management, and device miniaturization are examined. Future research directions involving perovskites, quantum dots, two-dimensional semiconductors, and first-principles computational approaches are also outlined. This review provides a concise perspective on the technological evolution and future development of high-performance LED devices.

Light-emitting diodes, Semiconductor materials, GaN, Micro-LED, Optoelectronics.

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