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The emergence of new materials and fabrication techniques provides progress in the development of advanced photonic and communication devices. Transition metal dichalcogenides (e.g., molybdenum disulfide, MoS2) are novel materials possessing unique physical and chemical properties promising for optical applications. In this paper, a metasurface composed of particles made of bulk MoS2 is proposed and numerically studied considering its operation in the near‐infrared range. In the bulk configuration, MoS2 has a layered structure being a uniaxial anisotropic crystal demonstrating an optical birefringence property. It is supposed that the large‐scale and uniform MoS2 layers are synthesized in a vertical‐standing morphology, and then they are patterned into a regular 2D array of disks to form a metasurface. The natural anisotropy of MoS2 is utilized to realize the splitting of electric and magnetic dipole modes of the disks while optimizing their geometric parameters to bring the desired modes into overlap. At the corresponding resonant frequencies, the metasurface behaves as either an electric or a magnetic mirror, depending on the polarization of incident light. Based on the extraordinary reflection characteristics of the proposed metasurface, it can be considered an alternative to traditional mirrors and optical splitters when designing compact and highly efficient metadevices, which provide polarization and phase manipulation of electromagnetic waves on a subwavelength scale. [ABSTRACT FROM AUTHOR]

Polarization plays a critical role in optical systems that range from optical communications to imaging, lithography, metrology, and data storage. Thus, in systems that need to generate a certain polarization state, a light source (e.g., laser) is combined with polarization control elements such as polarizers, polarizing beam splitters, and waveplates. Similarly, in systems requiring polarization state detection, such elements are combined with photodetectors. There is currently a trend toward miniaturized optical systems. This motivates the question of how to achieve what may be argued as an ultimate level of miniaturization: a single chip that can both generate light with a prescribed polarization state and detect the polarization state of light impinging upon it. This paper demonstrates this via vertical cavity surface emitting lasers (VCSELs) with on‐facet metasurfaces. Two classes of devices are demonstrated. The first class uses high‐index dielectric metasurfaces (amorphous silicon nanofins), whereas the second class uses plasmonic metasurfaces (aluminum bilayer gratings). Each can operate as a laser (to generate) and as a photodetector (to detect) circularly or linearly polarized light. [ABSTRACT FROM AUTHOR]

A novel polarisation beam splitter (PBS) with a high extinction ratio in a broad band has been proposed and realised by cascading a bent directional coupler and a low-loss transverse-magnetic (TM)-pass polariser based on a subwavelength grating. The realised PBS has a footprint as small as 3 × 22.5 μm, a high extinction ratio (>20 dB) and a low excess loss (∼1 dB) are obtained over a broad band of ∼60 nm for both transverse-electric and TM polarisations. [ABSTRACT FROM AUTHOR]