Acoustic guiding and subwavelength imaging with sharp bending by sonic   crystal
  A sharp bending scheme for the self-collimation of acoustic waves is proposed by simply truncating the sonic crystals. An all-angle and wide-band 90{\deg}-bending wave guide is demonstrated with nearly perfect transmissions for Gaussian beams at a wide range of incident angles. A 90{\deg}-bended imaging for a point source with a subwavelength resolution of 0 0.37{\lambda} is also realized by the proposed structure. These results will find applicability in the manipulation of acoustic waves by sonic crystals. 
Bo Li, Ke Deng, and Heping Zhao
physics.class-ph cond-mat.mtrl-sci