Wavelength and Pulsewidth Tunable Flexible CsPbBr ₃ Perovskite Microlasers by Mechanical Stress Modulation

ABSTRACT Strain‐induced wavelength‐tunable flexible lasers hold considerable promise in wearable devices and multifunctional electronic skin. Furthermore, their dynamic pulse parameter adjustability with picosecond‐level temporal resolution provides extended potential in high‐precision dynamic monitoring, high‐speed anti‐interference communication, and precision sensing. Here, we report a flexible CsPbBr 3 perovskite microlaser with spectral tunability of 1.59 nm in wavelength and 14 ps in laser pulsewidth through mechanical stress modulation. The device exhibits a low threshold density of <2 µJ/cm 2 , a high respond speed with a delay time of <70 ps, and an ultrashort optical pulse with a minimum duration of 10.8 ps. The strain‐induced evolution of the gain‐switched pulsed laser outputs, including pulsewidth, delay time, and photon decay were systematically explored, for the first time, by taking the strain–photon synergetic coupling mechanism into account. Additionally, the stress dependences of the laser pulse behaviors are physically revealed by theoretical simulations using the Hamiltonian matrix combined with rate equations. Our results provide not only a better understanding of lasing in flexible perovskite microcavity systems under stress, but also a new platform for high‐precision stress monitoring by picosecond‐level pulsewidth sensing.