We report the focusing of a normally incident plane wave of $405\mathrm{nm}$ through a Ag/dielectric annular ring structure, using finite-difference time domain analysis. We first study the dependency of the focusing efficiency on slit width when the incident wave is transmitted through a single ring whose slit is filled with a dielectric. Then, light focusing by the multiple-ring structure is investigated as a function of the dielectric thickness. It is observed that the focusing is tunable between near-field and quasi-far-field regimes in the Ag/dielectric layered annular ring structure. Also, the focal intensities are remarkably enhanced by the addition of the dielectric layer, showing a Fabry–Perot-like resonance with respect to the thickness of the dielectric layer. The controllable near-field and far-field focusing offers more flexibility for applications of future nano-optic devices.

© 2010 Optical Society of America

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

Related Journal Articles

• Standing-wave surface-plasmon resonances with overhanging zero-order metal gratings (JOSAA)
• Light propagation and scattering in stratified media: a Green’s tensor approach (JOSAA)
• Splitting and radiation of a surface plasmon by resonant ionization in a thin semiconductor coating (JOSAB)
• Coupling of Surface-Plasmon Polaritons to Directional Far-Field Radiation by an Individual Surface Protrusion (AO)
• Photonic crystal sensor based on surface waves for thin-film characterization (OL)

Related Conference Papers

• All-Electrical, Room Temperature Surface Plasmon Generation Using Quantum Cascade Lasers
• Surface Plasmon Enhanced Metal Nanoparticle-Dye Random Laser
• SERS Substrates Produced by Tailor-made Nanoparticles
• Dispersion Behavior of Surface Waves on Metal Wires in the Terahertz Frequency Range
• Coupling between Surface Plasmons in Subwavelength Hole Arrays