Broadband acoustic transmission enhancement(ATE)is realized for a periodically structured stiff plate without any opening that is conventionally thought to be only capable of supporting narrowband ATE,by introducing l...Broadband acoustic transmission enhancement(ATE)is realized for a periodically structured stiff plate without any opening that is conventionally thought to be only capable of supporting narrowband ATE,by introducing locally resonant(LR)elements.This exotic phenomenon is interpreted by analyzing the vibration pattern of the structure-induced LR modes,and is well modeled by a simple"spring-mass"system which reveals the contribution of the LR effect to the important broadband performance.Our findings should help to better understand the physical mechanism of ATE and may have potential impact on ultrasonic applications such as broadband acoustic filters or compact acoustic devices in subwavelength scale.展开更多
We propose a multi-layer structure for concealing an electromagnetic sensing system (a sensor is wrapped witha transparent protective layer),using single-negative (SNG) materials whose material parameters are complete...We propose a multi-layer structure for concealing an electromagnetic sensing system (a sensor is wrapped witha transparent protective layer),using single-negative (SNG) materials whose material parameters are completely independent of those of the host matrix as well as the concealed system.The numerical results show that only three different kinds of SNG materials are sufficient to yield the cloaking effect even in the presence of weak loss.This may significantly facilitate the experimental realization of a well-performing sensor-cloaking device.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 10904068,10834009,11174138,11174139Research Fund for the Doctoral Program(for new scholar)of Higher Education of China under Grant No 20100091120039A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Broadband acoustic transmission enhancement(ATE)is realized for a periodically structured stiff plate without any opening that is conventionally thought to be only capable of supporting narrowband ATE,by introducing locally resonant(LR)elements.This exotic phenomenon is interpreted by analyzing the vibration pattern of the structure-induced LR modes,and is well modeled by a simple"spring-mass"system which reveals the contribution of the LR effect to the important broadband performance.Our findings should help to better understand the physical mechanism of ATE and may have potential impact on ultrasonic applications such as broadband acoustic filters or compact acoustic devices in subwavelength scale.
基金Supported by the National Basic Research Program of China under Grant No 2011CB707900the National Natural Science Foundation of China under Grant Nos 10804050,10874086,10834009 and 10904068.
文摘We propose a multi-layer structure for concealing an electromagnetic sensing system (a sensor is wrapped witha transparent protective layer),using single-negative (SNG) materials whose material parameters are completely independent of those of the host matrix as well as the concealed system.The numerical results show that only three different kinds of SNG materials are sufficient to yield the cloaking effect even in the presence of weak loss.This may significantly facilitate the experimental realization of a well-performing sensor-cloaking device.
