Two-path phonon interference resonance induces a stop band in a silicon crystal matrix with a multilayer array of embedded nanoparticles

Article

关键词: THERMAL-CONDUCTIVITY;    PHOTONIC CRYSTALS;    SIMULATION;    TRANSPORT;    SCATTERING;    DYNAMICS;   

DOI  :  10.1103/PhysRevB.102.024301

来源: SCIE

【 摘 要 】

In this work, we report a mechanism of stop-band formation in a multilayer array of germanium nanoparticles embedded in a crystalline silicon matrix. When only a single layer of nanoparticles is embedded, the local resonance, induced by the destructive interference between two different phonon wave paths, gives rise to several sharp and significant transmittance dips. On the other hand, when the number of the layers of embedded nanoparticles further increases to ten, a stop band with complete phonon reflection is formed due to the two-path resonance Bragg-type phonon interference. The wave packet simulations further uncover that the stop band originates from the collective phonon resonances in the embedded nanoparticles layers. Compared with the traditional stop-band formation mechanism that is the single-path Bragg reflection, the two-path phonon-interference resonance mechanism has a significant advantage in not requiring the strict periodicity in the embedded nanoparticles multilayer array. We also demonstrate that the stop band can significantly suppress thermal conductance in the low-frequency regime. Our work provides a robust, scalable, and easily modulable stop-band formation mechanism, which opens a degree of freedom for phononics-related heat control.

【 授权许可】

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