Perovskite Lasers: Ultralow‐Threshold Continuous‐Wave Room‐Temperature Crystal‐Fiber/Nanoperovskite Hybrid Lasers for All‐Optical Photonic Integration (Adv. Mater. 12/2021)

In article number 2006819, Chien‐Chih Lai and co‐workers report the first demonstration of a diode‐pumped ultralow‐threshold continuous‐wave room‐temperature perovskite laser, by coating MAPbI3 nanocrystallites onto a high‐quality yttrium aluminum garnet (YAG) crystal fiber. The atomically smooth crystal fiber not only serves as a perfect microcavity for ultralow‐loss optical resonance but also facilitates heat dissipation toward robust laser devices, outperforming previously reported structures. This readies the ground for electrically driven lasers for all‐optical photonic integration.