【摘要】 为了更好地了解表面增强拉曼光谱(SERS)的机制,并进一步提高增强因子,研制了具有高稳定性的纳米劈裂装置及芯片。结合纳米劈裂技术及SERS技术,在拉曼光谱测量的同时能非常精确地操纵两纳米电极间的距离以观察相应拉曼光谱强度的变化。发现拉曼光谱强度依赖于纳米电极的间距以及激光的偏振化方向。在利用两纳米电极作为增强体的基础上引入了纳米门电极,并观察偏置电压下的门电极对拉曼光谱信号的影响。实验结果表明,拉曼光谱信号的强度强烈地依赖于纳米门电极上所施加的偏置电压。实验为增强拉曼信号提供了新的方法,同时为拉曼光谱增强机制的理论研究提供了参考数据。更多还原

【Abstract】 In order to better understand the mechanism of surface enhanced Raman spectroscopy(SERS) and further improve the Raman enhancement factor,a strategy which combines SERS and mechanical controllable break junctions(MCBJ) is employed.With such a strategy,the gap width between two nanoelectrodes can be adjusted precisely during the period of SERS measurement.The dependence of SERS intensity on the gap width and the incident laser polarization are investigated.Moreover,a nano gate-electrode with adjustable bias voltage is introduced,and the gate electrode effect to the Raman signal intensity is investigated in system.The experimental results demonstrate that the Raman signal intensity critically depends on the biased gate voltage,which provide a new method to enhance the Raman signal and benefit the theory investigation for the Raman enhancement mechanism.更多还原