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Analytic Optimization of Near-Field Optical Chirality Enhancement.

ABSTRACT: We present an analytic derivation for the enhancement of local optical chirality in the near field of plasmonic nanostructures by tuning the far-field polarization of external light. We illustrate the results by means of simulations with an achiral and a chiral nanostructure assembly and demonstrate that local optical chirality is significantly enhanced with respect to circular polarization in free space. The optimal external far-field polarizations are different from both circular and linear. Symmetry properties of the nanostructure can be exploited to determine whether the optimal far-field polarization is circular. Furthermore, the optimal far-field polarization depends on the frequency, which results in complex-shaped laser pulses for broadband optimization.

SUBMITTER: Kramer C

PROVIDER: S-EPMC5319396 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Analytic Optimization of Near-Field Optical Chirality Enhancement.

Kramer Christian C Schäferling Martin M Weiss Thomas T Giessen Harald H Brixner Tobias T

ACS photonics 20170125 2

We present an analytic derivation for the enhancement of local optical chirality in the near field of plasmonic nanostructures by tuning the far-field polarization of external light. We illustrate the results by means of simulations with an achiral and a chiral nanostructure assembly and demonstrate that local optical chirality is significantly enhanced with respect to circular polarization in free space. The optimal external far-field polarizations are different from both circular and linear. S ...[more]

PMID: 28239617

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