Center for Terahertz Research, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
Opt Lett. 2010 Nov 1;35(21):3544-6. doi: 10.1364/OL.35.003544.
Laser-induced plasma acoustic waves are enhanced under the illumination of single-cycle terahertz (THz) radiation, making THz-enhanced acoustics (TEA) a useful method for THz wave detection. During a single-cycle THz pulse with its peak field of 100 kV/cm, a pressure enhancement of 10% is observed throughout the acoustic spectrum up to 140 kHz, and the TEA signal is found to increase linearly with THz wave intensity. By using dual-color laser excitation to manipulate free electron drift, it is possible to modulate the enhanced acoustic signal and recover a coherent THz time-domain waveform by simply "listening" to the plasma.
激光诱导等离子体声波在单周期太赫兹（THz）辐射的照射下得到增强，使得太赫兹增强声学（TEA）成为一种有用的太赫兹波检测方法。在峰值场强为 100 kV/cm 的单周期太赫兹脉冲作用下，在整个声谱范围内（高达 140 kHz），观察到压力增强了 10%，并且 TEA 信号被发现与太赫兹波强度呈线性增加。通过使用双色激光激发来操纵自由电子漂移，可以调制增强的声信号，并通过简单地“监听”等离子体来恢复相干的太赫兹时域波形。
