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Featuring low threshold current, circular beam profile, and scalable fabrication, vertical cavity surface emitting lasers (VCSELs) have made indispensable contributions to the development of modern optoelectronic technologies. Manipulation of electromagnetic fields with emerging flat optical structures, namely metasurfaces, offers new opportunities to minimize complex optical systems into ultra-compact dimensions. Here, we proposed and experimentally demonstrated Vertical Cavity Metasurface-Emitting Lasers (VCMELs) through the monolithic integration of high-index metasurfaces, characterized by their remarkable spatial controllability over the laser beams. Such wafer-level monolithic integration of metasurfaces through VCSELs-compatible technology not only considerably simplifies the assembling process but also preserves the laser characteristics, with 2 great potential to promote various wide-field applications of VCSELs such as optical data communication, ultra-compact light detection and ranging (LiDAR), 3D sensing, and directional displays. Introduction: Vertical-cavity surface emitting lasers (VCSELs) have experienced a soaring development over the last 30 years, particularly after the demonstration of the first continuous-wave (cw) room-temperature device. 1-3 Their unique features such as low-power consumption, circular beam profile, wafer-level testing, large-scale two-dimensional (2D) array have made them the most versatile laser sources for a large number of applications ranging from optical communications, to instrumentation, as well as laser manufacturing and sensing. 4-6 The exploding application demands and the rapidly growing markets pose a longstanding challenge to further improve their performance while realizing precise beam control. In this context, the replacement of the top reflector with resonant structures and the incorporation of photonic crystal have been extensively employed to tune the emission, achieve high brightness,respectively. Meanwhile, considerable attention has been paid to improve the beam quality of the VCSELs, for example, by preventing high-order transverse modes 7-11 .Despite the fact that single-fundamental-mode laser can be realized by limiting the active region with a reduced oxide aperture, strong diffraction effect produces highly

Whole-body vibration exercise is a safe and effective method that can improve the mobility, knee extensor strength, balance and the general health status in the frail elderly.

The coordination compound Eu(DAF)2(NO3)3 (1, DAF = 4,5‐diazafluorene), which shows strong red fluorescence, has been synthesized and characterized. The luminescence‐quenching effect of 1 has been applied to the detection of water in CH3CN. For the first time, the response mechanism has been uncovered through the confirmation of the structure of the resultant nonluminous compound [Eu(NO3)2(H2O)5](NO3)(DAF)2·H2O (2). The replacement of the coordinated DAF ligands by the added water led to quenching of the emission of the EuIII ion and the simultaneous enhancement of the ligand emission. X‐ray powder diffraction and thermogravimetric analyses also confirmed this mechanism. Theoretical calculations by the semi‐empirical method revealed the origin of the absorption spectra of 1. This fluorometric detection of trace amounts of water in CH3CN by 1 is a direct, rapid, and sensitive method.

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