Allowing subwavelength-scale-digitization of optical wavefronts to achieve complete control of light at interfaces, metasurfaces are particularly suited for the realization of planar phase-holograms that promise new applications in high-capacity information technologies. Similarly, the use of orbital angular momentum of light as a new degree of freedom for information processing can further improve the bandwidth of optical communications. However, due to the lack of orbital angular momentum selectivity in the design of conventional holograms, their utilization as an information carrier for holography has never been implemented. Here we demonstrate metasurface orbital angular momentum holography by utilizing strong orbital angular momentum selectivity offered by meta-holograms consisting of GaN nanopillars with discrete spatial frequency distributions. The reported orbital angular momentum-multiplexing allows lensless reconstruction of a range of distinctive orbital angular momentum-dependent holographic images. The results pave the way to the realization of ultrahigh-capacity holographic devices harnessing the previously inaccessible orbital angular momentum multiplexing.

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

Controlling light properties with diffractive planar elements requires full-polarization channels and accurate reconstruction of optical signal for real applications. Here, we present a general method that enables wavefront shaping with arbitrary output polarization by encoding both phase and polarization information into pixelated metasurfaces. We apply this concept to convert an input plane wave with linear polarization to a holographic image with arbitrary spatial output polarization. A vectorial ptychography technique is introduced for mapping the Jones matrix to monitor the reconstructed metasurface output field and to compute the full polarization properties of the vectorial far field patterns, confirming that pixelated interfaces can deflect vectorial images to desired directions for accurate targeting and wavefront shaping. Multiplexing pixelated deflectors that address different polarizations have been integrated into a shared aperture to display several arbitrary polarized images, leading to promising new applications in vector beam generation, full color display and augmented/ virtual reality imaging.