Dynamic nonreciprocity in loss-compensated piezophononic media Articles uri icon

publication date

  • March 2018

issue

  • 3 (034033)

volume

  • 9

International Standard Serial Number (ISSN)

  • 2331-7019

abstract

  • Violating time-reversal symmetry enables one to engineer nonreciprocal structures for isolating and rectifying sound and mechanical vibrations. Rectifying sound is commonly achieved in nonlinear media, but the operation is inherently linked to weak and distorted signals. Here, we show how a pronounced electron-phonon coupling in linear piezophononic media under electrical bias can generate full mechanical rectification of broad spectral width, which permits the isolation of pulsed vibrations while keeping the wave-front shape fully intact. In this context, we deliberately show how the acoustoelectric effect can provide active loss compensation against lattice anharmonicity and thermoelastic damping. Further, our predictions confirm tunable nonreciprocity at an ultralarge contrast ratio, which should open the doors for future mechanical diodes and compact ultrasonic transducers for sensing and imaging.

keywords

  • Acoustic phonons
    Elasticity
    Electron-phonon coupling
    Piezoelectricity
    Fluid Dynamics
    Acoustic metamaterials
    Diodes
    Functional materials