Structured light for focusing surface plasmon polaritons.
We propose a structureless method for focusing surface plasmon polaritons (SPPs) on a flat metal film under illumination of radially polarized cogwheel-like structured light beams. Without metal structures, the locally induced SPPs can further be propagated following the predefined patterns to form symmetric focal spots with dimensions beyond diffraction limit. Benefiting from the radial polarization, this method can be employed to pattern various center-symmetric evanescent distributions for generating SPPs reconfigurably. The SPPs will be propagating and focusing in radial directions.
Hu
Z J
ZJ
Institute of Modern Optics, Key Laboratory of Optoelectronic Information Science & Technology, Ministry of Education of China, Nankai University, Tianjin 300071, People's Republic of China.
Tan
P S
PS
Zhu
S W
SW
Yuan
X-C
XC
D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D008670:Metals / Q000737:chemistry*; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods*; D012542:Scattering, Radiation; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
D008670:Metals