基于人工结构板的声贝塞尔束的相位调控(特邀)  

Phase Manipulation of Acoustic Bessel Beam Based on Artificial Structure Plate(Invited)

作　　者：罗立成 李恒毅 柯满竹[1] 刘正猷[1] LUO Licheng;LI Hengyi;KE Manzhu;LIU Zhengyou(School of Physics and Technology,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学物理科学与技术学院,武汉430072

出　　处：《光子学报》2022年第1期207-215,共9页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.11890701,11974262,11774275)。

摘　　要：理论及数值模拟了人工结构板对声贝塞尔束相位拓扑阶数的灵活调控。基于惠更斯原理推导了平面波及贝塞尔束入射到刻有镂空阿基米德螺旋栅的金属板后出射波的声场分布。结果表明,当平面波从结构板的正反两向入射时,可分别得到带相反拓扑阶数的贝塞尔束;当贝塞尔束从结构板的正反两向入射时,可获得升阶或降阶的出射贝塞尔束。数值模拟声场分布对理论分析进行验证,进一步发现,升高工作频率至人工结构板对应基频的倍数,会得到对入射波高倍数相位阶数的调控。本文提出的贝塞尔束声场调控方法有望推动轨道角动量在信息传递及编解码中的应用。Acoustic communication has been widely used underwater due to its relatively low loss.However,acoustic wave doesn’t have the physical properties of spin and polarization like electromagnetic wave,which makes it impossible to broaden the channel capacity by these ways. Meanwhile,orbital angular momentum provides a new option for acoustic communication as a new degree of freedom independent from time and frequency. In this case, vortex beams, which carry the orbital angular momentum,are attracting great attention for their potential application of making acoustic waves transfer more information at the same frequency. As one kind of the vortex beams,Bessel beams have the characteristics of highly-localized energy and non-diffraction. In this manuscript,an artificial structure plate with hollow Archimedes spiral grids has been designed to manipulate the phase of the output wave with different incident acoustic wave. The spacing between the spiral grid is equal to the wavelength corresponding to the fundamental frequency. The flexible manipulation of the acoustic Bessel beam’s phase and topological order assisted by this plate have been studied theoretically and numerically. Based on Huygens principle,the distribution of output acoustic field produced by the incident plane wave or Bessel beam which travel through the plate from the front or the back side is derived. The result shows that when the plane wave transmits the plate from the opposite directions,the outgoing Bessel beam with opposite topological order can be obtained separately;when Bessel beam transmits the plate from the opposite direction,the outgoing Bessel beam with ascending or reduced order can be obtained. When the working frequency increases to a multiple of the fundamental frequency corresponding to the artificial structure plate,the higher multiple phase and topological order manipulation for the incident wave can be obtained.Similar result can also be derived by increasing the spacing between the spiral grid to a multiple of the wavelength. T

关 键 词：声贝塞尔束 声人工结构板 相位调控 角动量 拓扑荷 

分 类 号：O424[理学—声学]