title: A nonlinear acoustic metamaterial: Realization of a backwards-traveling second-harmonic sound wave.
abstract: An ordinary waveguide with periodic vibration plates and side holes can realize an acoustic metamaterial that simultaneously possesses a negative bulk modulus and a negative mass density. The study is further extended to a nonlinear case and it is predicted that a backwards-traveling second-harmonic sound wave can be obtained through the nonlinear propagation of a sound wave in such a metamaterial.
authors.affiliation: Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Quan
authors.affiliation: Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Qian
authors.affiliation: Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Xiaozhou
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Xiufen
authors.initials: X
authors.lastname: Gong