摘要
An underwater acoustic metasurface with sub-wavelength thickness is designed for acoustic wavefront manipulation.In this paper, a pentamode lattice and a frequency-independent generalized acoustic Snell's law are introduced to overcome the limitations of narrow bandwidth and low transmittance. The bulk modulus and effective density of each unit cell can be tuned simultaneously, which are modulated to guarantee the achievement of refractive index profile and high transmission. Here, we actualize anomalous refraction, generation of non-diffracting Bessel beam, sub-wavelength flat focusing,and surface wave conversion by constructing inhomogeneous acoustic metasurface. This design approach has potential applications in medical ultrasound imaging and underwater acoustic communications.
An underwater acoustic metasurface with sub-wavelength thickness is designed for acoustic wavefront manipulation.In this paper, a pentamode lattice and a frequency-independent generalized acoustic Snell's law are introduced to overcome the limitations of narrow bandwidth and low transmittance. The bulk modulus and effective density of each unit cell can be tuned simultaneously, which are modulated to guarantee the achievement of refractive index profile and high transmission. Here, we actualize anomalous refraction, generation of non-diffracting Bessel beam, sub-wavelength flat focusing,and surface wave conversion by constructing inhomogeneous acoustic metasurface. This design approach has potential applications in medical ultrasound imaging and underwater acoustic communications.
作者
Ying Liu
Yi-Feng Li
Xiao-Zhou Liu
刘颖;李义丰;刘晓宙(College of Computer Science and Technology,Nanjing Tech University;Key Laboratory of Modern Acoustics,Ministry of Education,Nanjing University;Key Laboratory of Modern Acoustics,Ministry of Education,Institute of Acoustics and School of Physics,Nanjing University)
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.61571222 and 11474160)
the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20161009)
the Six-Talent Peaks Project of Jiangsu Province,China
