Printing polarization and phase at the optical diffraction limit: near- and far-field optical encryption

Song, Qinghua; Khadir, Samira; Vézian, S.; Damilano, B.; Mierry, P. de; Chenot, Sébastien; Brändli, Virginie; Laberdesque, Romain; Wattellier, Benoît; Genevet, Patrice

doi:10.1515/nanoph-2020-0352

Cited by 22 publications

(18 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The simultaneous manipulation of the polarization and wavefront in an optical system is important for various polarization-related optical systems in the fields of polarization imaging, encryption, target recognition, information communication, and biomedicine. − Metasurfaces are ultrathin planar structures based on subwavelength artificial unit cells. Unlike traditional methods that shape the wavefront via propagation-phase accumulations, metasurfaces control the direction of propagation by introducing a phase discontinuity condition on the surface of the structure by a series of unit cells .…”

mentioning

confidence: 99%

Chirality-Assisted Aharonov–Anandan Geometric-Phase Metasurfaces for Spin-Decoupled Phase Modulation

Xie

Guo

et al. 2021

ACS Photonics

View full text Add to dashboard Cite

In this work, a quasi-nondispersive and spin-decoupled phase modulation strategy was proposed based on the chiral structure. Owing to the spindependent response of the chiral structure, the evolution of the Aharonov− Anandan (AA) geometric phase can be controlled by tuning different structural parameters independently. Additionally, the chiral structure was designed nonresonant or weak-resonant to minimize the influence of strong resonant absorption and large dispersive propagation phase shift, leading to an efficiently quasi-nondispersive phase modulation. To prove the validity of the strategy, a series of umbrella-shaped reflection-type metal−insulator−metal structures were designed as the unit cells and simulated with the finite element method. Moreover, the metasurfaces were designed based on such unit cells to generate broadband orbital angular momentums with different topological charges and spin-switchable holograms, respectively. Simulated and experimental results are in good agreement with the theoretical results. To the best of our knowledge, broadband spindependent phase modulation has been achieved without intentionally merging other types of phases for the first time in this work. We believe that this strategy provides a flexible approach for complex spin-or polarization-related applications in optical communication, integrated optics, optical sensing, and other related fields.

show abstract

mentioning

confidence: 99%

Chirality-Assisted Aharonov–Anandan Geometric-Phase Metasurfaces for Spin-Decoupled Phase Modulation

Xie

Guo

et al. 2021

ACS Photonics

View full text Add to dashboard Cite

show abstract

“…The phase pattern encoded in different polarization channels at both two spaces have been demonstrated, where the near field phase profile can be extracted using quadriwave lateral shearing interferometry technique. [ 52 ] In the nonlinear optical regime, a plasmonic metasurface composed of diatomic meta‐molecules was proposed to encode an intensity image in the real‐space based on the interference between the second harmonic generation waves in a meta‐molecule. And a holographic image was reconstructed in the k ‐space due to the spin‐controlled geometric phase.…”

Section: Introductionmentioning

confidence: 99%

Polarization and Holography Recording in Real‐ and k‐Space Based on Dielectric Metasurface

Zhao

Geng

et al. 2021

Adv Funct Materials

View full text Add to dashboard Cite

The diverse design freedom and mechanisms of metasurfaces motivate the manipulation of polarization in an ultrashort distance with subwavelength resolution and make metasurfaces outperform conventional polarization optical elements. However, in order to enhance the information capability and encryption security of metasurface holograms, polarization manipulation together with multiplexing technologies are still highly desired. Here, a birefringent dielectric metasurface with the capability of encoding a grayscale image in real‐space based on Malus's law by utilizing the inhomogeneous polarization distribution and realizing the reconstruction of a vectorial holographic image in k‐space with the help of the phase profiles of different polarization components of output light is demonstrated. This novel functionality is realized by exploiting the manipulation of polarization and phase of output light simultaneously offered by the dielectric metasurface. The proposed method may enhance the information capability and security level of applications such as the anticounterfeiting and encryption.

show abstract

“…As phases of reconstructed images are unable to be detected directly, encoding vectorial distributions by the phase difference can further enhance the security of information encryption. The phase distributions are usually detected indirectly [ 42,43 ] by transforming them into the intensity changes. In this work, only under the incidence of a linearly polarized light with specific phase difference between the RCP and LCP components, can extra encrypted images be correctly unmasked from the overlapping area of the two reconstructed images.…”

Section: Introductionmentioning

confidence: 99%

Multiplexing Vectorial Holographic Images with Arbitrary Metaholograms

Wan

Yang

Feng

et al. 2021

Advanced Optical Materials

View full text Add to dashboard Cite

Metasurfaces achieving arbitrary phase profiles within ultrathin thickness, emerge as miniaturized, ultracompact, and kaleidoscopic nanophotonic platforms. However, it is often required to segment or interleave independent subarray metasurfaces to multiplex holograms in a single nanodevice, which in turn affects the device's compactness and channel capacity. Here, a flexible strategy is proposed for multiplexing vectorial holographic images by controlling the phase distributions of holographic images in far field. Benefitting from precisely controlling the phase difference of reconstructed images through the modified Gerchberg–Saxton algorithm, two different holographic images are independently designed for the circular light by two interleaved metasurfaces and an extra vectorial hologram is flexibly encrypted in far field without additional set of structures on the metasurface plane. An unlimited number of polarization can be achieved in the holographic image and additional information can be decrypted when different polarization‐dependent holographic images overlap. By continually varying phase difference between the incident right and left circular polarized light, the image within the overlap area can be modulated. The silicon dielectric metahologram with record absolute multiplexed efficiency (>25%) is achieved in the experiment. This technique, as far as it is known, promises an enormous data capacity as well as a high level of information security.

show abstract

Printing polarization and phase at the optical diffraction limit: near- and far-field optical encryption

Cited by 22 publications

References 46 publications

Chirality-Assisted Aharonov–Anandan Geometric-Phase Metasurfaces for Spin-Decoupled Phase Modulation

Chirality-Assisted Aharonov–Anandan Geometric-Phase Metasurfaces for Spin-Decoupled Phase Modulation

Polarization and Holography Recording in Real‐ and k‐Space Based on Dielectric Metasurface

Multiplexing Vectorial Holographic Images with Arbitrary Metaholograms

Contact Info

Product

Resources

About