Experimental demonstration of an acoustic magnifying hyperlens

[gy gao]

Jensen Li1,3, Lee Fok1,3, Xiaobo Yin1,2, Guy Bartal1 & Xiang Zhang1,2

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AbstractAcoustic metamaterials can manipulate sound waves in
surprising ways, which include collimation, focusing, cloaking, sonic
screening and extraordinary transmission1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14. Recent theories suggested that imaging below the
diffraction limit using passive elements can be realized by acoustic
superlenses or magnifying hyperlenses15, 16. These could markedly
enhance the capabilities in underwater sonar sensing, medical
ultrasound imaging and non-destructive materials testing. However,
these proposed approaches suffer narrow working frequency bands and
significant resonance-induced loss, which hinders them from successful
experimental realization. Here, we report the experimental
demonstration of an acoustic hyperlens that magnifies subwavelength
objects by gradually converting evanescent components into propagating
waves. The fabricated acoustic hyperlens relies on straightforward
cutoff-free propagation and achieves deep-subwavelength resolution
with low loss over a broad frequency bandwidth.

http://www.nature.com/nmat/journal/v8/n12/full/nmat2561.html
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