Han Haoxue, Li Baowen, Volz Sebastian, Kosevich Yuriy A
CNRS, UPR 288 Laboratoire d'Energétique Moléculaire et Macroscopique, Combustion (EM2C), Grande Voie des Vignes, 92295 Châtenay-Malabry, France.
Ecole Centrale Paris, Grande Voie des Vignes, 92295 Châtenay-Malabry, France.
Phys Rev Lett. 2015 Apr 10;114(14):145501. doi: 10.1103/PhysRevLett.114.145501. Epub 2015 Apr 6.
We introduce a novel ultracompact nanocapacitor of coherent phonons formed by high-finesse interference mirrors based on atomic-scale semiconductor metamaterials. Our molecular dynamics simulations show that the nanocapacitor stores coherent monochromatic terahertz lattice waves, which can be used for phonon lasing-the emission of coherent phonons. Either one- or two-color phonon emission can be realized depending on the geometry of the nanodevice. The two-color regime of the interference phonon nanocapacitor originates from the different incidence-angle dependence of the transmission of longitudinal and transverse phonons at the respective interference antiresonances. Coherent phonon storage can be achieved by an adiabatic cooling the nanocapacitor initially thermalized at room temperature or by the pump-probe optical technique. The linewidth narrowing and the computed relative phonon participation number confirm strong phonon confinement in the ultracompact interference nanocavity by an extremely small amount of resonance defects. The emission of coherent terahertz acoustic beams from the nanocapacitor can be realized by applying a tunable reversible stress, which shifts the frequencies of the interference antiresonances.
我们介绍了一种基于原子尺度半导体超材料的由高精细度干涉镜形成的新型超紧凑相干声子纳米电容器。我们的分子动力学模拟表明，该纳米电容器存储相干单色太赫兹晶格波，可用于声子激光——相干声子的发射。根据纳米器件的几何形状，可以实现单色或双色声子发射。干涉声子纳米电容器的双色机制源于纵向和横向声子在各自干涉反共振处传输的不同入射角依赖性。相干声子存储可以通过对最初在室温下热化的纳米电容器进行绝热冷却或通过泵浦 - 探测光学技术来实现。线宽变窄和计算出的相对声子参与数证实了在超紧凑干涉纳米腔中通过极少量的共振缺陷实现了强声子限制。通过施加可调谐的可逆应力，可以实现纳米电容器发射相干太赫兹声束，该应力会改变干涉反共振的频率。
