Ultrafast acoustic phonon ballistics in semiconductor heterostructures
Ultrafast acoustic phonon ballistics in semiconductor heterostructures
复制标题
DOI：
10.1103/physrevlett.78.3358
复制
发表时间：
1997-04-28
影响因子：
8.6
通讯作者：
Kohler, K
中科院分区：
文献类型：
--
作者：
Baumberg, JJ;Williams, DA;Kohler, K
利用双色超快表面偏转光谱，我们证明了声声子波包的时间分辨观测，这些声子波包是从单个埋在地下的砷化镓量子阱中发出的。通过相干非平衡形变势，在高度受限的区域(大于或等于10 nm厚)内的预选深度处产生纵向声学声子脉冲，这是以前在此类结构中未观察到的。随后在地表以亚皮秒分辨率进行的探测分辨了传播的高波矢量弹道声子和准弹道声子或“蛇”声子，这些声子随后合并成准扩散声子脉冲。
Using a two-color ultrafast surface deflection spectroscopy, we demonstrate the time-resolved observation of acoustic phonon wave packets emitted from a single buried GaAs quantum well. A longitudinal acoustic phonon pulse is generated at a preselected depth within a highly confined region (greater than or equal to 10 nm thick) through the coherent nonequilibrium deformation potential which was previously unobserved in such structures. Subsequent detection with subpicosecond resolution at the surface resolves propagating high-wave-vector ballistic phonons sind quasiballistic or "snake" phonons which subsequently merge into a quasidiffusive phonon pulse.