Advances and future of Spaser nanoprobes: from fundamental research to practical applications

Modern biological and medical research increasingly depends on the application and development of high-performance luminescent probes. Among them, Spaser (surface plasmon amplification by stimulated emission of radiation) nanoprobes have emerged as a promising subwavelength laser emission platform, offering distinctive advantages such as ultra-narrow emission linewidths, nanoscale structural dimensions, exceptional brightness, and excellent biocompatibility. These unique properties position Spaser nanoprobes as powerful tools in advanced applications including multicolor imaging, high-throughput detection, and precision bioanalysis. This feature article provides a comprehensive overview of the development and technological evolution of Spaser nanoprobes, tracing their journey from fundamental research to practical implementation. Emphasis is placed on recent advances in structural design, performance optimization, and bioimaging applications. By highlighting key breakthroughs and emerging strategies, this review aims to offer valuable insights and design guidelines for the continued advancement and broader application of Spaser nanoprobes in biomedical science and technology.