We investigate both experimentally and numerically a complex structure, where ＇face-to-face＇ Helmholtz resonance cavities （HRCs） are introduced to construct a one-dimensional acoustic grating. In this system, pair...We investigate both experimentally and numerically a complex structure, where ＇face-to-face＇ Helmholtz resonance cavities （HRCs） are introduced to construct a one-dimensional acoustic grating. In this system, pairs of HRCs can intensely couple with each other in two forms： a bonding state and an anti-bonding state, analogous to the character of hydrogen molecule with two atoms due to the interference of wave functions of sound among the acoustic local-resonating structures. The bonding state is a ＇bright＇ state that interferes with the Fabry-Pbrot resonance mode, thereby causing this state to break up into two modes as the splitting of the extraordinary acoustic transmission peak. On the contrary, the anti-bonding state is a ＇dark＇ state in which the resonance mode remains entirely localized within the HRCs, and has no contribution to the acoustic transmission.展开更多
Extraordinary acoustic transmission （EAT） has been investigated in a tunable bull＇s eye structure. We demonstrate that the transmission coefficient of acoustic waves can be modulated by a grating structure. When th...Extraordinary acoustic transmission （EAT） has been investigated in a tunable bull＇s eye structure. We demonstrate that the transmission coefficient of acoustic waves can be modulated by a grating structure. When the grating is located at a distance of 0.5 mm from the base plate, the acoustic transmission shows an 8.77-fold enhancement compared to that by using a traditional bull＇s eye structure. When the distance increases to 1.5 mm, the transmission approaches zero, indicating a total reflection. Thus, we can make an efficient modulation of acoustic transmission from 0 to 877%. The EAT effects have been ascribed to the coupling of structure-induced resonance with the diffractive wave and the waveguide modes, as well as the Fabry-Perot resonances. As a potential application, the modulation of far-field collimation is illustrated in the proposed bull＇s eye structure.展开更多
基金Supported by the National Basic Research Program of China under Grant Nos 2012CB921503,2013CB632904 and 2013CB632702the National Natural Science Foundation of China under Grant No 1134006+2 种基金the Natural Science Foundation of Jiangsu Province under Grant No BK20140019the Project Funded by the Priority Academic Program Development of Jiangsu Higher Educationthe China Postdoctoral Science Foundation under Grant Nos 2012M511249 and 2013T60521
文摘We investigate both experimentally and numerically a complex structure, where ＇face-to-face＇ Helmholtz resonance cavities （HRCs） are introduced to construct a one-dimensional acoustic grating. In this system, pairs of HRCs can intensely couple with each other in two forms： a bonding state and an anti-bonding state, analogous to the character of hydrogen molecule with two atoms due to the interference of wave functions of sound among the acoustic local-resonating structures. The bonding state is a ＇bright＇ state that interferes with the Fabry-Pbrot resonance mode, thereby causing this state to break up into two modes as the splitting of the extraordinary acoustic transmission peak. On the contrary, the anti-bonding state is a ＇dark＇ state in which the resonance mode remains entirely localized within the HRCs, and has no contribution to the acoustic transmission.
基金Project supported by the National Basic Research Program of China(Grant No.2012CB921504)the National Natural Science Foundation of China(GrantNos.11104139,11274171,11274099,and 11204145)+1 种基金SRFDP(Grant Nos.20110091120040,20120091110001,and 20130091130004)the NaturalScience Foundation of Jiangsu Province,China(Grant No.BK2011542)
文摘Extraordinary acoustic transmission （EAT） has been investigated in a tunable bull＇s eye structure. We demonstrate that the transmission coefficient of acoustic waves can be modulated by a grating structure. When the grating is located at a distance of 0.5 mm from the base plate, the acoustic transmission shows an 8.77-fold enhancement compared to that by using a traditional bull＇s eye structure. When the distance increases to 1.5 mm, the transmission approaches zero, indicating a total reflection. Thus, we can make an efficient modulation of acoustic transmission from 0 to 877%. The EAT effects have been ascribed to the coupling of structure-induced resonance with the diffractive wave and the waveguide modes, as well as the Fabry-Perot resonances. As a potential application, the modulation of far-field collimation is illustrated in the proposed bull＇s eye structure.
