Huang Wenyu, Qian Wei, El-Sayed Mostafa A
Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400, USA.
J Am Chem Soc. 2006 Oct 18;128(41):13330-1. doi: 10.1021/ja064328p.
Femtosecond laser irradiation of assembled nanoprisms on a quartz substrate at their strong absorbing surface plasmon resonance frequency causes their propulsion from the substrate. SEM and AFM show that the particles fly while keeping their prismatic shape, but they decrease in size by an amount that can be calculated assuming atomic sublimation. Several mechanisms are mentioned, but the sublimation mechanism, which rapidly builds up pressure under the particle and propels it away from substrate, is discussed in detail. From the kinetic energy given to the flying nanoparticle, an initial velocity of approximately 160 m/s ( approximately 360 miles/h) is calculated. The dependence of the observed flying mechanism on the rate of energy deposition (i.e., with nanosecond vs femtosecond laser pulses) is discussed.
在石英衬底上以其强吸收表面等离子体共振频率对组装好的纳米棱柱进行飞秒激光辐照，会使其从衬底上推进。扫描电子显微镜（SEM）和原子力显微镜（AFM）显示，粒子在飞行过程中保持棱柱形状，但尺寸会减小，减小的量可通过假设原子升华来计算。文中提到了几种机制，但详细讨论了升华机制，即该机制在粒子下方迅速产生压力并将其从衬底上推离。根据赋予飞行纳米粒子的动能，计算出初始速度约为160米/秒（约360英里/小时）。还讨论了观察到的飞行机制对能量沉积速率（即纳秒与飞秒激光脉冲）的依赖性。
