Centre for Advanced Nanotechnology, University of Toronto, Toronto, Canada.
Nanotechnology. 2010 Jun 11;21(23):235502. doi: 10.1088/0957-4484/21/23/235502. Epub 2010 May 17.
Metal and semiconductor nanorods polarized by an external electric field tend to align parallel to this field. We derived the equation of motion for this alignment, taking into account electrostatic forces, thermal fluctuations and viscous resistance of the liquid the nanorods are suspended in. It was solved for a strong ac electric field, as well as for the combination of strong dc and weak ac fields. The results were used for calculations of the capacity of the nanorod solution, its frequency dispersion and dependence on the field strength. Modification of the nanorod absorption spectra under the influence of an electric field was also considered. It was shown that metal nanorods in laser radiation, with the frequency belonging to the interval between longitudinal and transverse plasmon modes, tend to align perpendicular, rather than parallel, to the optical electric field.
受外部电场极化的金属和半导体纳米棒往往会与该电场平行排列。我们考虑了静电作用力、热涨落以及纳米棒悬浮在其中的液体的粘性阻力，推导出了这种排列的运动方程。我们还针对强交流电场以及强直流电场和弱交流电场的组合情况对方程进行了解析。研究结果用于计算纳米棒溶液的电容、频率色散以及对场强的依赖性。还考虑了电场影响下纳米棒吸收光谱的变化。研究表明，在激光辐射中，对于属于纵向和横向等离子体模式之间的频率间隔的金属纳米棒，其趋向于垂直于而不是平行于光电场排列。
