Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093, United States.
ACS Nano. 2011 Jun 28;5(6):5100-6. doi: 10.1021/nn201181p. Epub 2011 Apr 22.
Surface plasmons efficient excitation is typically expected to be strongly constrained to transverse magnetic (TM) polarized incidence, as demonstrated so far, due to its intrinsic TM polarization. We report a designer plasmonic metamaterial that is engineered in a deep subwavelength scale in visible optical frequencies to overcome this fundamental limitation, and allows transverse electric (TE) polarized incidence to be strongly coupled to surface plasmons. The experimental verification, which is consistent with the analytical and numerical models, demonstrates this enhanced TE-to-plasmon coupling with efficiency close to 100%, which is far from what is possible through naturally available materials. This discovery will help to efficiently utilize the energy fallen into TE polarization and drastically increase overall excitation efficiency of future plasmonic devices.
表面等离激元的有效激发通常被预期强烈地局限于横向磁场（TM）偏振入射，这是由于其固有 TM 偏振。我们报告了一种设计的等离子体超材料，它在可见光频率的深亚波长尺度上被工程化，以克服这一基本限制，并允许横向电场（TE）偏振入射被强烈地耦合到表面等离激元。实验验证与分析和数值模型一致，证明了这种增强的 TE 到等离子体的耦合具有接近 100%的效率，这远远超出了现有材料的可能性。这一发现将有助于有效地利用落入 TE 偏振的能量，并极大地提高未来等离子体器件的整体激发效率。
