Abstract

We propose the use of polarization mapping as a tool to better separate the effects of plasmonic coupling from the local refractive index for molecular imaging and biosensing using gold nanoparticles. Polarization mapping allows identification of the orthogonal excitation mode when the particle dimer orientation is unknown, as may be the case when using plasmonic nanoparticles for cell labeling. This information can be used to sense relative changes in the dielectric environment, or for absolute dielectric sensing with additional a priori interparticle distance information. First, the theoretical scattering by nanoparticle pairs is modeled under parallel and orthogonal polarization orientations and increasing interparticle separation. Second, polarization mapping of substrate bound nanoparticles using dark-field microspectroscopy is investigated as a method to isolate the individual plasmonic coupling modes associated with a pair of nanoparticles without reorientation of the sample. The results of this study provide useful insight toward potential avenues for monitoring distances using plasmonic nanoparticles and sensing the local refractive index using nanoparticle pairs when the pair orientation is not known, as may be the case when using nanoparticles for cell receptor labeling.

© 2011 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 (3)

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