Subterahertz phonon dynamics in acoustic nanocavities
Subterahertz phonon dynamics in acoustic nanocavities
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DOI：
10.1103/physrevlett.97.115502
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发表时间：
2006-09-15
影响因子：
8.6
通讯作者：
Lemaitre, A.
中科院分区：
文献类型：
--
作者：
Huynh, A.;Lanzillotti-Kimura, N. D.;Lemaitre, A.
我们报告了用皮秒声学直接测定纳米腔中受限声子的动态行为。我们在亚太赫兹范围内提供了宽带，高分辨率的传输幅度曲线，并在三个连续的停止带中提供了共振传输峰的证据，与声学模拟的定量一致。我们进一步证明了在腔峰处的传输时间在纳秒范围内，反映了谐振声子在腔层内的强约束。另一方面，皮秒的传输时间是在停止带测量的，比任何构成材料都短，这是在光子晶体和宏观声子系统中众所周知的隧道效应。
We report a direct determination of the dynamic behavior of confined acoustic phonons in nanocavities by picosecond acoustics. We provide the broadband, high resolution transmission amplitude curve in the subterahertz range, and we give evidence of resonant transmission peaks in three successive stop bands, in quantitative agreement with acoustic simulations. We furthermore demonstrate transit times in the nanosecond range at the cavity peaks reflecting the strong confinement of resonant phonons within the cavity layer. On the other hand, picosecond transit times are measured in the stop band, shorter than in any of the constituting materials, a tunneling effect well known both in photonic crystals and in macroscopic phononic systems.