Room-temperature Continuous-Wave Upconversion White Microlaser Using a Rare-earth-Doped Microcavity

Abstract

White laser covering the visible color spectrum is critical in various applications including vivid display, holographic imaging, and light-based version of Wi-Fi, but it is still challenging to realize a white microlaser due to the rigorous requirement for the balance between the optical gain and feedback in a wide wavelength range. Here, we employ thulium, erbium, and ytterbium elements corporately for the upconversion white lasing by an individual ultrahigh-quality (Q) (up to 10 8 ) doped microcavity with microwatt thresholds for the red, green, and blue lasers. To the best of our knowledge, it is the first rare-earthelement-based room-temperature continuous-wave white microlaser. This microlaser also exhibits relatively stable chromaticity over 180 min, which makes it possible for practical applications.

Lanthanide-Doped Upconversion Nanoparticles: Exploring A Treasure Trove of NIR-Mediated Emerging Applications

“…Most recently, Jiang et al claimed the first report of a Tm–Er–Yb codoped microsphere cavity for a white-light emissive continuous microlaser that is operational at room temperature and exhibits stable chromaticity for over 180 min. They reported the thresholds for red, green, and blue lasers to be 90, 500, and 300 μW, respectively . The emergence of room temperature operating UCNP microlasers opens the potential for advancements in numerous cutting-edge applications, including those already discussed in this article.…”

Backscattering-Induced Chiral Absorption in Optical Microresonators

“…When we slowly pulled the fiber from both sides, the diameter of the fiber will decrease to around 1.5 μm . The microspheres were fabricated using a carbon dioxide laser at the tip of a single-mode fiber. , First, we tapered the fiber to a diameter of less than 10 μm with the help of gravity, and the fiber was knocked off to generate a fiber tip. By utilizing the surface tension, the silica tip curled to form a sphere.…”

Multifunctional Laser-Induced Bubble Microresonator for Upconversion Emission Enhancement

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