Emerging and perspectives in microlasers based on rare-earth ions activated micro-/nanomaterials

Microlasers have drawn considerable attention for applications in future optoelectronic nanoscience and nanotechnology, owing to the capability of scaling physical dimension of devices down to micro-/nanometer level. Currently, the most popular optical gain micro-/nanomaterials for microlasers are inorganic semiconductors, organic dyes and polymers, and organic-inorganic hybrid perovskites. However, these optical gain micro-/nanomaterials are faced with severe issues of either complicated manufacturing process or low stability under air, thermal, and photoirradiation ambient. Comparatively, rare-earth (RE) ions-activated micro-/nanomaterials show unique merits for building-up microlasers, including low-cost fabrication, high environmental stability, abundant spectrum bands (ultraviolet to mid-infrared), high photoluminescence quantum yield (PLQY), etc. Recently, new RE ions-activated luminescent materials have been exploited as low surface defects and high PLQY in terms of diverse micro-/nanostructures, which have stimulated great progress in emerging RE ions activated microlasers, in combination with design and fabrication of novel optical feedback micro-/nanoresonators. Herein, recent advances in RE ions activated microlasers are reviewed from the aspects of Materials and Theories (including optical gain media and feedback micro-/nanomaterials), as well as some enlightening works on Upconverting Pumped Microlasers and Down-Shifting/Converting Pumped Microlasers; finally, future Perspectives are given by providing inspiration for exploitation of RE ions activated micro-/ nanolasers with desired performances.

Automated summary

Microlasers have attracted significant attention due to their ability to scale devices down to the micro-/nanometer level, with rare-earth (RE) ions-activated micro-/nanomaterials showing unique advantages such as low-cost fabrication, high environmental stability, and high photoluminescence quantum yield. Recent advances in RE ions activated microlasers have led to great progress in the field, with new materials and structures stimulating further development and exploration in this area.