Slablab A, Le Xuan L, Zielinski M, de Wilde Y, Jacques V, Chauvat D, Roch J-F
Laboratoire de Photonique Quantique et Moléculaire, Ecole Normale Supérieure de Cachan and CNRS, UMR 8537, F-94235 Cachan Cedex, France.
Opt Express. 2012 Jan 2;20(1):220-7. doi: 10.1364/OE.20.000220.
We show that a dimer made of two gold nanospheres exhibits a remarkable efficiency for second-harmonic generation under femtosecond optical excitation. The detectable nonlinear emission for the given particle size and excitation wavelength arises when the two nanoparticles are as close as possible to contact, as in situ controlled and measured using the tip of an atomic force microscope. The excitation wavelength dependence of the second-harmonic signal supports a coupled plasmon resonance origin with radiation from the dimer gap. This nanometer-size light source might be used for high-resolution near-field optical microscopy.
我们表明，由两个金纳米球组成的二聚体在飞秒光激发下表现出显著的二次谐波产生效率。对于给定的颗粒尺寸和激发波长，当两个纳米颗粒尽可能接近接触时，会出现可检测到的非线性发射，这是通过原子力显微镜的尖端进行原位控制和测量的。二次谐波信号对激发波长的依赖性支持了具有来自二聚体间隙辐射的耦合等离子体共振起源。这种纳米尺寸的光源可用于高分辨率近场光学显微镜。
