†The Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education, School of Physics and TEDA Applied Physics Institute, Nankai University, Tianjin 300071, P.R. China.
‡Tsinghua-Foxconn Nanotechnology Research Center, Department of Physics, Tsinghua University, Beijing 100084, P.R. China.
Nano Lett. 2015 May 13;15(5):2951-7. doi: 10.1021/nl5047973. Epub 2015 Apr 17.
Polarizers provide convenience in generating polarized light, meanwhile their adoption raises problems of extra weight, cost, and energy loss. Aiming to realize polarizer-free polarized light sources, herein, we present a plasmonic approach to achieve direct generation of linearly polarized optical waves at the nanometer scale. Periodic slot nanoantenna arrays are fabricated, which are driven by the transition dipole moments of luminescent semiconductor quantum dots. By harnessing interactions between quantum dots and scattered fields from the nanoantennas, spontaneous emission with a high degree of linear polarization is achieved from such hybrid antenna system with polarization perpendicular to antenna slot. We also demonstrate that the polarization is engineerable in aspects of both spectrum and magnitude by tailoring plasmonic resonance of the antenna arrays. Our findings will establish a basis for the development of innovative polarized light-emitting devices, which are useful in optical displays, spectroscopic techniques, optical telecommunications, and so forth.
起偏器在产生偏振光方面提供了便利，但它们的采用也带来了额外的重量、成本和能量损失等问题。为了实现无偏光器的偏振光源，本文提出了一种等离子体方法，可在纳米尺度上直接产生线性偏振光。我们制作了周期性狭缝纳米天线阵列，由发光半导体量子点的跃迁偶极子驱动。通过利用量子点与纳米天线散射场之间的相互作用，从与天线狭缝垂直的方向上实现了具有高度线性偏振的自发发射。我们还证明，通过调整天线阵列的等离子体共振，可以在光谱和幅度两方面对偏振进行调控。我们的研究结果将为开发创新的偏振发光器件奠定基础，这些器件在光学显示、光谱技术、光通信等领域都有重要应用。
