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Coordinate-transformation-inspired optical devices have been mostly examined in the continuous-wave regime: the performance of an invisibility cloak, which has been demonstrated for monochromatic excitation, %would inevitably is likely to deteriorate for short pulses. Here we investigate pulse dynamics of flexural waves propagating in transformed plates. We propose a practical realization of a waveshifter and a rotator for flexural waves based on the coordinate transformation method. Time-resolved measurements reveal how the waveshifter deviates a short pulse from its initial trajectory, with no reflection at the bend and no spatial and temporal distortion of the pulse. Extending our strategy to cylindrical coordinates, we design a wave rotator. We demonstrate experimentally how a pulsed plane wave is twisted inside the rotator, while its wavefront is recovered behind the rotator and the pulse shape is preserved, with no extra time delay. We propose the realization of the dynamical mirage effect, where an obstacle appears oriented in a deceptive direction.
In this paper, a novel design concept for active self-adaptive metamaterial (ASAMM) plates is proposed based on an active self-adaptive (ASA) control strategy guided by the particle swarm optimization (PSO) technique. The ASAMM plates consist of an e
The paper studies the initial boundary value problem related to the dynamic evolution of an elastic beam interacting with a substrate through an elastic-breakable forcing term. This discontinuous interaction is aimed to model the phenomenon of attach
As 2D materials with subwavelength structures, elastic metasurfaces show remarkable abilities to manipulate elastic waves at will through artificial boundary conditions. However, the application prospects of current metasurfaces may be restricted by
We present here how a coherent perfect absorber-laser (CPAL) enabled by parity-time ($mathcal{PT}$)-symmetry breaking may be exploited to build monochromatic amplifying devices for flexural waves. The fourth order partial differential equation govern
The effect of asymmetric functionally graded material on the edge resonance and the Fano resonance in semi-infinite FGM plates are reported in this work. The edge resonance is weakened by the material perturbation and the complete mode conversion is