Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
ACS Nano. 2012 Feb 28;6(2):1786-94. doi: 10.1021/nn204845z. Epub 2012 Jan 25.
This paper reports the fabrication and characterization of three-dimensional (3D) multiscale Au particles with different aspect ratios. Increasing the length of the particles resulted in excitation of a longitudinal mode and two different transverse modes having different multipolar orders. The multipolar orders increased for both longitudinal and transverse modes as the aspect ratio increased. Finite-difference time-domain calculations revealed that the structural asymmetry of the 3D anisotropic particles were the reason for the two distinct transverse plasmon resonances. When the 3D structural change occurred at the ends of the multiscale particle, however, the optical response showed two resonances in the longitudinal direction and only a single resonance in the transverse direction.
本文报道了具有不同纵横比的三维（3D）多尺度金颗粒的制备和表征。随着颗粒长度的增加，激发了一个纵向模式和两个具有不同多极阶数的不同横向模式。随着纵横比的增加，纵向和横向模式的多极阶数都增加了。时域有限差分计算表明，3D 各向异性颗粒的结构不对称是两个不同的横向等离子体共振的原因。然而，当多尺度颗粒的两端发生 3D 结构变化时，光学响应在纵向方向显示出两个共振，而在横向方向仅显示出一个共振。
