Abstract-Vector characterization of zero-order terahertz Bessel beams with linear and circular polarizations

https://www.nature.com/articles/s41598-017-12524-y

As a kind of special beams, Bessel beams are always a research hot spot in optics due to its non-diffractive and self-healing properties. Here, zero-order terahertz (THz) Bessel beams with linear and circular polarizations are generated by using a THz quarter wave plate and Teflon axicons with different opening angles. By applying a THz digital holographic imaging system, the evolutions of the transverse (E x , E y ) and longitudinal (E z ) electric fields are coherently measured and analyzed during the propagation processes of the THz Bessel beams. The vectorial Rayleigh diffraction integral is used to accurately reproduce the amplitude, phase, and non-diffractive feature of each polarization component for the THz Bessel beams. With varying opening angles of the axicons, the focal spots, diffraction-free ranges, and Gouy phase shifts of the THz Bessel beams are compared and discussed. The experiment and simulation results provide a comprehensive view for exactly understanding peculiar features of THz Bessel beams.

Abstract-Laguerre–Gauss beams versus Bessel beams showdown: peer comparison

Job Mendoza-Hernández, Maximino Luis Arroyo-Carrasco, Marcelo David Iturbe-Castillo, and Sabino Chávez-Cerda

We present for the first time a comparison under similar circumstances between Laguerre–Gauss beams (LGBs) and Bessel beams (BB), and show that the former can be a better option for many applications in which BBs are currently used. By solving the Laguerre–Gauss differential equation in the asymptotic limit of a large radial index, we find the parameters to perform a peer comparison, showing that LGBs can propagate quasi-nondiffracting beams within the same region of space where the corresponding BBs do. We also demonstrate that LGBs, which have the property of self-healing, are more robust in the sense that they can propagate further than BBs under similar initial conditions.

© 2015 Optical Society of America

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Abstract-The Generation of Bessel Beam and Its Application in Millimeter Wave Imaging

Hongfu Meng, Bo Xiang, Jinglei Zhang, Wenbin Dou, Yanzhong Yu
http://link.springer.com/article/10.1007%2Fs10762-013-0037-9#

In this paper, the zero-order Bessel beam at W band is generated by using a diagonal horn, a convex lens, and an axicon. The generated Bessel beam has a beam spot size of 5.5mm and can propagate with a distance longer than 100mm. Several imaging experiments with the generated zero-order Bessel beam are done. The results show that the millimeter wave imaging system with the generated Bessel beam can be used to detect object as small as 1mm.