Metasurface-assisted orbital angular momentum carrying Bessel-Gaussian Laser: proposal and simulation

Abstract

Bessel-Gaussian beams have distinct properties of suppressed diffraction divergence and self-reconstruction. In this paper, we propose and simulate metasurface-assisted orbital angular momentum (OAM) carrying Bessel-Gaussian laser. The laser can be regarded as a Fabry-Perot cavity formed by one partially transparent output plane mirror and the other metasurface-based reflector mirror. The gain medium of Nd:YVO4 enables the lasing wavelength at 1064 nm with a 808 nm laser serving as the pump. The sub-wavelength structure of metasurface facilitates flexible spatial light manipulation. The compact metasurface-based reflector provides combined phase functions of an axicon and a spherical mirror. By appropriately selecting the size of output mirror and inserting mode-selection element in the laser cavity, different orders of OAM-carrying Bessel-Gaussian lasing modes are achievable. The lasing Bessel-Gaussian0, Bessel-Gaussian01+, Bessel-Gaussian02+ and Bessel-Gaussian03+ modes have high fidelities of ~0.889, ~0.889, ~0.881 and ~0.879, respectively. The metasurface fabrication tolerance and the dependence of threshold power and output lasing power on the length of gain medium, beam radius of pump and transmittance of output mirror are also discussed. The obtained results show successful implementation of metasurface-assisted OAM-carrying Bessel-Gaussian laser with favorable performance. The metasurface-assisted OAM-carrying Bessel-Gaussian laser may find wide OAM-enabled communication and non-communication applications.

Reconfigurable and tunable twisted light laser

“…In general, a Fabry-Perot (FP) cavity formed by two mirrors is employed to construct a laser 64 – 66 . For a laser with cavity that is cylindrically symmetric, the lasing beam profile is also circularly symmetric often best solved using the Laguerre-Gaussian (LG) modal decomposition.…”

“…In order to realize either LG 0 , + l or LG 0 , −l lasing, one may break the degeneracy of a standard laser cavity. One possible way is to insert an extra carefully designed mode-selection element (MSE) into the cavity 64 , 66 . Using pump control to produce desired modes or developing micro-chip laser could avoid the use of MSE inside the cavity 51 , 52 , 57 .…”

On-chip silicon photonic signaling and processing: a review

“…Also, silicon photonics has been considered to be a powerful platform for broadband mid-infrared photonics [304,305]. Additionally, some more interesting applications, such as optical coherence tomography [306,307], ultrafast optical ranging [308], spatial mode or structured light manipulation [309][310][311][312][313][314][315][316][317][318][319], optical phased array and LiDAR [320][321][322][323][324] have also been widely studied. In future, it is believed that silicon photonics will facilitate more and more emerging advanced applications in a compact way with superior performance.…”

Digitized subwavelength surface structure on silicon platform for wavelength-/polarization-/charge-diverse optical vortex generation

“…Unlike ordinary light beams with a planar phasefront, the generation of optical vortices characterized by doughnut intensity pro les and helical phasefronts usually relies on bulky devices used for mode conversion, such as cylindrical lens pairs, spiral phase plates, diffractive optical elements, and spatial light modulators [41][42][43][44]. Additionally, resonator cavities, qplates, metamaterials and metasurfaces are also used for generating optical vortices [45][46][47][48][49][50][51][52]. Very recently, for the sake of miniaturization and integration, photonic integrated devices have been demonstrated to generate optical vortices [53][54][55][56][57][58][59][60][61][62][63][64][65].…”