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Time-reversing a monochromatic subwavelength optical focus by optical phase conjugation of multiply-scattered light.

ABSTRACT: Due to its time-reversal nature, optical phase conjugation generates a monochromatic light wave which retraces its propagation paths. Here, we demonstrate the regeneration of a subwavelength optical focus by phase conjugation. Monochromatic light from a subwavelength source is scattered by random nanoparticles, and the scattered light is phase conjugated at the far-field region by coupling its wavefront into a single-mode optical reflector using a spatial light modulator. Then the conjugated beam retraces its propagation paths and forms a refocus on the source at the subwavelength scale. This is the first direct experimental realisation of subwavelength focusing beyond the diffraction limit with far-field time reversal in the optical domain.

SUBMITTER: Park J

PROVIDER: S-EPMC5278350 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Time-reversing a monochromatic subwavelength optical focus by optical phase conjugation of multiply-scattered light.

Park Jongchan J Park Chunghyun C Lee KyeoReh K Cho Yong-Hoon YH Park YongKeun Y

Scientific reports 20170130

Due to its time-reversal nature, optical phase conjugation generates a monochromatic light wave which retraces its propagation paths. Here, we demonstrate the regeneration of a subwavelength optical focus by phase conjugation. Monochromatic light from a subwavelength source is scattered by random nanoparticles, and the scattered light is phase conjugated at the far-field region by coupling its wavefront into a single-mode optical reflector using a spatial light modulator. Then the conjugated bea ...[more]

PMID: 28134267

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