Generation of acoustic helical wavefronts using metasurfaces
نویسندگان
چکیده
In the following, we will consider two cylindrical waveguides separated by a device under test (DUT) of thickness s, the scattering parameters of which will be assessed. A loudspeaker is used to generate sound in the first (incident) waveguide, the second waveguide being closed with an anechoic termination, and four microphones are placed at locations xi at both sides of the interface to measure the sound pressures Pi = P (xi), as shown in Fig. (1). Mathematically, the pressures Pi are defined by:
منابع مشابه
Flat optics with designer metasurfaces.
Conventional optical components such as lenses, waveplates and holograms rely on light propagation over distances much larger than the wavelength to shape wavefronts. In this way substantial changes of the amplitude, phase or polarization of light waves are gradually accumulated along the optical path. This Review focuses on recent developments on flat, ultrathin optical components dubbed 'meta...
متن کاملAFRL-AFOSR-VA-TR-2016-0060 Wavefront engineering with phase discontinuities: designer interfaces for high performance planar opticalcomponents
The PI and his group opened up new directions of research: the generation of vector beams with metasurfaces that control amplitude, phase and polarization of wavefronts, the detection of wavefronts using metasurfaces, new metasurfaces for controlling surface plasmon wavefronts and high performance device applications of metasurfaces on graphene. In the vector beam area they generated radially p...
متن کاملVisible-frequency metasurfaces for broadband anomalous reflection and high-efficiency spectrum splitting.
Ultrathin metasurfaces have recently emerged as promising materials that have huge potential to enable novel, flat optical components, and surface-confined, miniature photonic devices. Metasurfaces offer new degrees of freedom in molding the optical wavefronts by introducing abrupt and drastic changes in the amplitude, phase, and/or polarization of electromagnetic radiation at the wavelength sc...
متن کاملDispersionless Manipulation of Reflected Acoustic Wavefront by Subwavelength Corrugated Surface
Free controls of optic/acoustic waves for bending, focusing or steering the energy of wavefronts are highly desirable in many practical scenarios. However, the dispersive nature of the existing metamaterials/metasurfaces for wavefront manipulation necessarily results in limited bandwidth. Here, we propose the concept of dispersionless wavefront manipulation and report a theoretical, numerical a...
متن کاملDecoupling optical function and geometrical form using conformal flexible dielectric metasurfaces
Physical geometry and optical properties of objects are correlated: cylinders focus light to a line, spheres to a point and arbitrarily shaped objects introduce optical aberrations. Multi-functional components with decoupled geometrical form and optical function are needed when specific optical functionalities must be provided while the shapes are dictated by other considerations like ergonomic...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2016