A subwavelength metal grating is designed to generate axially symmetric polarized beams (ASPBs) in the visible region, and a simulation based on the rigid coupled wave algorithm (RCWA) is performed to optimize the grating. The ring-shaped grating is manufactured by electron beam lithography (EBL), nanometer-imprint and plasma etching technologies. An azimuthally polarized beam is obtained with the grating under the 632.8 nm He–Ne laser radiation, which can be transferred to a radially polarized beam or other ASPBs with wave plates. Based on the broad band feature of the grating, this method is practical and reliable in realizing ASPBs.

The self-organized nanograting manufactured by irradiating the transparent materials with the femtosecond laser has aroused wide interests in photonic applications in recent years. Although the mechanism of nanograting formatting has not yet been fully understood, the essential property of the optical birefringence can be precisely acquired by controlling the energy fluence of the femtosecond laser. In this paper, we proposed a novel application of the self-organized nanograting in a division-of-focal-plane polarimeter. Based on the rigid-coupled-wave algorithm, the optical characteristics of the nanograting and the polarimeter were comprehensively analyzed and discussed.

From Er3+/Tm3+ co-doped tellurite glass microspheres, simultaneous laser oscillation at 1.9 μm, and green and red fluorescence emissions with three photons upconversion luminescence were obtained. The microsphere was pumped by a low-cost 1550 nm broadband amplified spontaneous emission source instead of a bulky and expensive tunable laser. It as a non-polarized light provided a wide wavelength range and the multiple wavelengths resonant absorption was obviously observed from the transmission spectra. The use of broadband source made the entire microsphere laser more adaptively stable to withstand the vibration interference and temperature variations. The coupled threshold power was as low as 1.5 mW. It was demonstrated that the Er3+ ions acted as sensitizers to efficiently absorb the pump photons and transfer energy to Tm3+ ions. Therefore, this approach would have potential applications in optical fiber lasers, sensors and lighting devices.

A full-Stokes polarization imaging method based on the self-organized grating array was presented. By focusing the ultra-fast laser with moderate fluence into fused silica, the self-organized grating array was fabricated, featuring the optical properties similar to wave plates. A set of four independent polarization measurements were simultaneously acquired with designed grating array mounted in the focal plane of an imaging detector. Experimental results including the device fabrication, calibration and optimization were presented. Finally, a principle verification experiment was implemented for our polarization imaging method.

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