1] Key Lab of Micro-/Nano- Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China [2] The Beijing Key Laboratory for Nano-Photonics and Nano-Structure (NPNS), Center for Condensed Matter Physics, Department of Physics, Capital Normal University, Beijing 100048, China.
1] Key Lab of Micro-/Nano- Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China [2] SZU-NUS Collaborative Innovation Center for Optoelectronic Science &Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Sci Rep. 2015 Feb 3;5:8207. doi: 10.1038/srep08207.
We investigated the near-field response in silver nanoparticle aggregates to the excitation of circular polarized light. In a right-angle trimer system, the local field intensity excited by right-hand circularly polarized light is almost one thousand times larger than the left-hand case. By analyzing the polarization and phase of the local field in plasmonic hotspots, we found this local circular dichroism is originated from the near-field interference excited by orthogonal polarized incident lights. The local circular dichroism can be tuned by the rotation of the third particle, the interparticle distance, and the dielectric environment. This phenomenon could also widely exist in more complicated nanoaggregates. These findings would benefit for resolving light handedness, and enhancing circular dichroism and optical activity.
我们研究了银纳米粒子聚集体在圆偏振光激发下的近场响应。在直角三聚体系统中，右手圆偏振光激发的局域场强度几乎比左手情况大一千倍。通过分析等离子体热点中局域场的偏振和相位，我们发现这种局域圆二色性源于正交偏振入射光激发的近场干涉。通过第三粒子的旋转、粒子间距离和介电环境可以调节局域圆二色性。这种现象也可能广泛存在于更复杂的纳米聚集体中。这些发现将有助于解决光手性问题，并增强圆二色性和旋光活性。
