Properties And Applications Of General Airy-like Beams

Diffraction-free beams, a special type of light beam, share the property that their cross-sectional intensity distributions remain unchanged when they propagate in the free space. Diffraction-free beams have attached much attention both in theoretical researches and experimental applications since the diffraction-free Bessel beam was discovered. In2007, the optical Airy beam, a kind of non-diffraction beam, is discovered and generated in experiments. It not only shares the same diffraction-free and self-healing properties as the conventional diffraction-free beams, but also enjoys its special property-self-bending propagation, which means that the intensity peak of Airy beam will displace along a quadratic curve when propagating. These innovative properties have attracted a lot of interests from researchers and been widely used in applications such as optical sweeps, optical micromanipulation and etc. Some researchers studied the superposition of Airy beams and the related topic of Airy beams in polar coordinates, and proposed Bessel-like beams and autofocusing Airy beams. These new beams play an important role in many applications. In this paper, based on Airy beam’s physics essence and theoretical analysis, the concept and properties of traditional Airy beams are reviewed. We have proposed, for the first time, a new type of beam—"Airy-like" beam, with a new degree of freedom of θ, by which Airy-like beam can be flexibly configured and designed. This new beam has the similar wavefront to the traditional Airy beam, but its wavefront is adjustable. The traditional Airy Beam can also be regarded as a special type of Airy-like beams. Airy-like beam’s self bending, non-diffraction and quasi-self-healing properties, which are related to the new parameter θ and thus flexibly adjustable, are discussed and studied. Then, the superposition of Airy-like beams is also discussed, especially the autofocusing beams generated from a kind of circular superposition of Airy-like beams. Some important physical quantities of Airy-like beam, such as Poynting vectors, angular momentums, focal fields and Wigner distribution functions (WDF), are theoretically analyzed and numerically simulated. At last, some applications or potentials of Airy-like beam are discussed.The paper is outlined as follows:In chapter1, non-diffraction beams’concept, definition and properties are briefly introduced. Some kinds of non-diffraction beams are also reviewed.In chapter2, Airy beam’s concept and definition is introduced. The related properties of self-bending, non-diffraction and self-healing are discussed.In chapter3, a new kind of beam—"Airy-like" beam—is proposed for the first time, with a new degree of freedom of6, based on physical analysis. The Airy-like beam’s self-bending, non-diffraction and quasi self-healing properties are studied.In chapter4, superposition of Airy-like beam and their properties are discussed and studied, especially, among which the autofocusing property originated from the circular superposition is included.In chapter5, some important physical quantities of Airy-like beam are theoretical deduced and numerical simulated, such as Poynting vectors, angular momentums, focal fields and WDF, for better understanding of the Airy-like beam.In chapter6, some applications and possible applications of Airy-like beam are discussed.In chapter7, a summary of this paper is presented.