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A dual-wavelength high-spectral-resolution lidar (HSRL) based on an iodine absorption filter and a field-widened Michelson interferometer (FWMI) has been developed to profile backscatter and extinction coefficients of aerosols and clouds accurately. This instrument was tested and calibrated on multiple observations in Hangzhou and Zhoushan, respectively, from August 2018 to April 2019. This paper discusses the design and the internal calibration method of the lidar system in detail, with several typical cases of observations and the analysis of these data products. The optical properties of urban aerosols in Hangzhou and the evolvement of clouds in Zhoushan are presented, respectively.

This paper presents two approaches to calibrate the overlap factor under inhomogeneous atmospheric condition without critical assumption and delivers detailed analysis about the retrieval errors of overlap profile in High-Spectral-Resolution-Lidar (HSRL). The first method employs an additional optical subsystem with different field-of-view, that is dual field-of-view HSRL, for the retrieval of overlap profile. The second method takes advantage of the difference of the result between the HSRL and Klett method, that is about the retrieval of backscatter coefficient for uncorrected lidar signal, to correct overlap profile. Surprisingly, two methods show very high-level consistency and stability of the result. It is potential that this technique would be an excellent solution for experimental determination of lidar overlap in ground-based HSRL.

We analytically and numerically investigate the dynamic propagation of the quadratically chirped Airy beams in right-handed material (RHM) and left-handed material (LHM) slabs. Based on the analytical expressions and numerical calculations, we find that through choosing the appropriate value of the quadratic chirp, one can modify the diffraction, the intensity distribution, the propagation path, and acceleration and deceleration of the quadratically chirped Airy beams to meet the actual usage accordingly. In addition, we also demonstrate the effect of the quadratic chirp on the Poynting vector and the angular momentum of the quadratically chirped Airy beams, respectively. Furthermore, we explore the gradient and scattering forces on a Rayleigh dielectric particles induced by the quadratically chirped Airy beams.

Through analytical derivation and numerical analysis, the propagation properties of the chirped Airy(CAi) beams in the gradient-index medium are investigated. The intensity and the phase distributions, the propagation trajectory and the Poynting vector of the CAi beams are demonstrated to investigate the propagation properties. Owing to the special and symmetrical refractive index profile of the gradient-index medium, the CAi beams propagate periodically. The effects of the distribution factor and the chirped parameter on the propagation of the CAi beams are analyzed. As the increasing of the distribution factor, the intensity distribution of the CAi beams is more scattering. However, with the chirped parameter increasing, the focusing property of the CAi beams strengthens. The variation of the chirped parameter can change the position of the peak intensity maximum, but it cannot alter the period of the peak intensity. The variations of the initial phase and the energy of the beams in the transverse plane expedite accordingly.

We present an investigation on the propagation properties of the chirped Airy vortex (CAiV) beams through slabs of left-handed materials (LHMs) and right-handed materials (RHMs). We discuss the influence of chirped parameter C on the propagation of the CAiV beams through LHM and RHM slabs. Our simulation results show that a maximum accelerated velocity appears during the propagation process. The intensity concentration of the CAiV beams increases with the absolute value of the chirped parameter. The peak intensity of the CAiV beams changes abruptly, and the chirped parameter plays an active role on the difference of the maximum and the minimum. In the energy flow, we find that the effects of the chirped parameter on the strength of the vortex are different at different propagation distances.

The detection of clouds and aerosols is important for climate research. Lidar has been widely used in atmospheric remote sensing research because of its high spatial and temporal resolution and ability to detect profiles. High spectral resolution lidar (HSRL) accurately calculates the optical properties of aerosols and clouds without relying on any assumptions. Based on the 532nm iodine HSRL system, the lidar ratio of the urban aerosol in Hangzhou is 40-50sr, and the average lidar ratio of the cirrus is 24.79sr, demonstrating that the HSRL system and retrieval algorithms accurately obtain the optical properties of clouds and aerosols.

With the transfer matrix method, analytical expressions of radially and azimuthally polarized chirped-Airy vortex beams (RPCAiVBs and APCAiVBs, respectively) through right-handed materials and left-handed materials are derived. We mainly discuss the effects of the radial and azimuthal polarizations as well as the effects of the chirped parameter on the propagation properties, including the propagation trajectory, the transverse intensity and the phase distributions, the peak intensity, the radiation forces, and the transverse orbital and spin currents of the RPCAiVBs and APCAiVBs in the x direction, the y direction, and their synthesizing direction. It is shown that the x, y, and synthesizing directions of the RPCAiVBs and APCAiVBs satisfy the vector synthesis rule, owing to the axial symmetry, and intensity modulation of the RPCAiVBs and APCAiVBs can be achieved by varying the chirped parameter.