摘要
In the backward propagation of acoustic waves, the direction of phase velocity is anti-parallel to that of group velocity. We propose a scheme to manipulate the backward propagation using a periodicM structure. The dynamic backward propagation process is further experimentally observed. It is demonstrated that the oblique incident plane wave moves backward when it travels through the periodical structure and the backward shift can be controlled within a certain range.
In the backward propagation of acoustic waves, the direction of phase velocity is anti-parallel to that of group velocity. We propose a scheme to manipulate the backward propagation using a periodicM structure. The dynamic backward propagation process is further experimentally observed. It is demonstrated that the oblique incident plane wave moves backward when it travels through the periodical structure and the backward shift can be controlled within a certain range.
基金
Supported by the National Natural Science Foundation of China under Grant Nos 11404245 and 11374231
the National High-Tech Research and Development Program of China under Grant No 2012AA022606
the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No 20130091130004
the National Key Scientific Instrument and Equipment Development Project of China under Grant No 2012YQ15021306
