Time reversal of ultrasound through a phononic crystal.
In this Letter, we experimentally investigate time reversal focusing through a phononic crystal consisting of a periodic square arrangement of steel rods in water. An acoustic pulse is transmitted through the medium, received at a transducer array, time reversed and backpropagated. Both spatial focusing and time compression are studied and compared with those obtained through an equivalent disordered medium. With the phononic crystal, we do not observe the "hyperfocusing effect" that is typical of time reversal through disordered samples.
Tourin
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Laboratoire Ondes et Acoustique, ESPCI, Université Paris VII, UMR 7587, 10 rue Vauquelin, 75005 Paris, France.
Van Der Biest
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Fink
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