Abstract

Sharp geometrical features in crescent-shaped plasmonic nanostructures facilitate electromagnetic hot spots that can be harnessed for sensitive detection of molecules and nanomaterials. For a given geometry of nanocrescent cylinder, the near-field optical resonance and enhancement are constants. It is desirable to tune this resonance and enhancement without altering the geometry of the nanocrescent cylinder. Herein, we numerically show how the near-field resonance and enhancement at the tip of a nanocrescent cylinder can be proximally tuned by incorporating a plasmonic nanostrip in the vicinity. Geometrical parameters, such as the nanocrescent cylinder–nanostrip distance (g) and length (l) of the nanostrip, were varied to tune the near-field optical properties. Our analysis revealed (i) an increment in near-field enhancement at the tip of the nanocrescent cylinder in the presence of a plasmonic nanostrip; (ii) a redshift in the dipolar plasmon mode accompanied by an increase in the near-field enhancement by decreasing g and increasing l, independently; and (iii) variation in the near-field enhancement of plasmonic modes as a function of the excitation angle. Such tunable plasmonic configurations offer capabilities to design wavelength-tuned optical devices without altering the base geometry.

© 2012 Optical Society of America

Full Article  |  PDF Article

References

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
Login to access OSA Member Subscription

Cited By

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
Login to access OSA Member Subscription

Figures (5)

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
Login to access OSA Member Subscription

Metrics

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
Login to access OSA Member Subscription