Sanchis-Alepuz Helios, Kosevich Yuriy A, Sánchez-Dehesa José
Wave Phenomena Group, Department of Electronic Engineering, Polytechnic University of Valencia, Camino de Vera, E-46022 Valencia, Spain.
Phys Rev Lett. 2007 Mar 30;98(13):134301. doi: 10.1103/PhysRevLett.98.134301. Epub 2007 Mar 29.
We demonstrate the existence of Bloch oscillations of acoustic fields in sound propagation through a superlattice of water cavities and layers of methyl methacrylate. To obtain the acoustic equivalent of a Wannier-Stark ladder, we employ a set of cavities with different thicknesses. Bloch oscillations are observed as time-resolved oscillations of transmission in a direct analogy to electronic Bloch oscillations in biased semiconductor superlattices. Moreover, for a particular gradient of cavity thicknesses, an overlap of two acoustic minibands occurs, which results in resonant Zener-like transmission enhancement.
我们证明了在声波通过水腔和聚甲基丙烯酸甲酯层的超晶格传播时存在声场的布洛赫振荡。为了获得与万尼尔 - 斯塔克阶梯等效的声学结构，我们采用了一组不同厚度的腔体。观察到布洛赫振荡表现为传输的时间分辨振荡，这与有偏置半导体超晶格中的电子布洛赫振荡直接类似。此外，对于特定的腔体厚度梯度，会出现两个声学微带的重叠，这导致了类似齐纳共振的传输增强。
