Rotational Doppler effect of composite vortex beams with tailored OAM spectra  

作　　者：YUTIAN LIANG RUIJIAN LI JIE ZHAO XINGYUAN LU TONG LIU ZHENGLIANG LIU YUAN REN CHENGLIANG ZHAO 

机构地区：[1]Department of Aerospace Science and Technology,Space Engineering University,Beijing 101416,China [2]School of Physical Science and Technology,Soochow University,Suzhou 215006,China [3]Department of Basic Course,Space Engineering University,Beijing 101416,China

出　　处：《Photonics Research》2024年第8期1665-1672,共8页光子学研究（英文版）

基　　金：National Natural Science Foundation of China(61805283,62173342)。

摘　　要：There recently has been increasing interest in the research and application of the rotational Doppler effect(RDE),which paves a promising way to detect rotating objects remotely.In order to obtain more information about the rotating object from the rotational Doppler signal,composite vortex beams by coaxial superposition of orbital angular momentum(OAM)modes are often used as the probe beam.However,to the best of our knowledge,the RDE of composite vortex beams with arbitrary OAM spectra has not yet been comprehensively studied.In this paper,the correspondence between the OAM spectrum of a probe beam and the frequency spectrum of a rotational Doppler signal is theoretically analyzed.It is explicitly revealed that the RDE frequency spectrum of scattered light is related to the product of two autocorrelation functions:one from the OAM spectrum of probe beam and the other from the spiral spectrum of rotating object.On the basis of this relation,one can regulate the RDE frequency spectrum on demand via tailoring the OAM spectrum of the probe beam.As a proof of concept we design a special composite vortex beam to eliminate the broadening of the RDE spectrum induced by misalignment.These findings are of practical value in applications such as remote sensing and optical metrology.

关 键 词：OAM COMPOSITE ROTATING 

分 类 号：O43[机械工程—光学工程]