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Cited by 301Metamaterials and Metasurfaces ApplicationsOrbital Angular Momentum in OpticsAdvanced Optical Imaging Technologies

The DOI matches its Crossref record; 49 of the 54 references it cites were found in a registry or an index; 7 of the 16 sources its claims cite were checked for support.

Polarization-Encrypted Orbital Angular Momentum Multiplexed Metasurface Holography

Open access
Zhou, Hongqiang, Sain, Basudeb, Wang, Yongtian, Schlickriede, Christian, Zhao, Ruizhe, Zhang, Xue, Wei, Qunshuo, Li, Xiaowei, Huang, Lingling, Zentgraf, Thomas·2020·ACS Nano
DOI 10.1021/acsnano.9b09814PMC PMC7254835
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Abstract

Metasurface holography has the advantage of realizing complex wavefront modulation by thin layers together with the progressive technique of computer-generated holographic imaging. Despite the well-known light parameters, such as amplitude, phase, polarization, and frequency, the orbital angular momentum (OAM) of a beam can be regarded as another degree of freedom. Here, we propose and demonstrate orbital angular momentum multiplexing at different polarization channels using a birefringent metasurface for holographic encryption. The OAM selective holographic information can only be reconstructed with the exact topological charge and a specific polarization state. By using an incident beam with different topological charges as erasers, we mimic a super-resolution case for the reconstructed image, in analogy to the well-known STED technique in microscopy. The combination of multiple polarization channels together with the orbital angular momentum selectivity provides a higher security level for holographic encryption. Such a technique can be applied for beam shaping, optical camouflage, data storage, and dynamic displays.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The paper demonstrates an all-dielectric birefringent metasurface that combines orbital angular momentum (OAM) selectivity with polarization multiplexing for holographic encryption. Holograms are reconstructed only when the illumination carries the matching topological charge and polarization, and OAM beams can also act as erasers to reveal finer image details in a STED-like manner.

Key findings

  • OAM-selective holograms were reconstructed only with the correct topological charge and polarization: “NATURE” appeared in the Txx channel for l = 40 with x-polarized illumination, and “SCIENCE” appeared in the Tyy channel for l = 20 with y-polarized illumination.
  • The reconstructed “NATURE” and “SCIENCE” images had peak signal-to-noise ratios of 29.11 dB and 29.83 dB, respectively.
  • In cross-polarization channels, a vortex array served as an OAM indicator, following l = m × lx + b, with lx set to 20 and five diffraction orders optimized while unwanted orders were suppressed.
  • A STED-like camouflage demonstration used l = 40 vortex illumination to reveal extra details, such as textures on grapes and a serrated edge on a leaf, compared with Gaussian-beam illumination.

Methods

  • The metasurface used silicon nanofins on a SiO2 substrate, with height and period fixed at 600 nm and 400 nm, respectively; length and width were swept from 80 to 280 nm for operation at 800 nm.
  • Design and optimization used rigorous coupled-wave analysis, and the Jones matrix was engineered to multiplex independent phase profiles across polarization channels with OAM-dependent phase terms.
  • Fabrication involved plasma-enhanced chemical vapor deposition of a 600 nm amorphous silicon film, electron beam lithography, chromium evaporation, lift-off, and inductively coupled plasma reactive ion etching.

Limitations

  • The paper states that a ring-like residual zero-order spot appeared experimentally because of the discrete metasurface and fabrication deviations from the theoretical design.
  • The paper states that vortex-beam illumination produced lower contrast than plane-wave illumination because the ring-shaped intensity profile reduced efficiency.
  • The paper states that zero-order spots remained in the holographic images due to fabrication inaccuracies and the discrete nature of the metasurface; it does not provide a systematic quantification of crosstalk or security across all possible OAM and polarization combinations.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1021/acsnano.9b09814

Cites

49 of 49 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

7 of 16 cited sources checked · 3 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    OAM selective holography has the potential to achieve optical data storage with complex security features by using OAM mode orthogonality and conservation.

    “Using the properties of orthogonality between different OAM modes and the OAM conservation law, OAM selective holography has the potential to achieve optical data storage with complex security features.”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [43] Ren, 2019, Metasurface Orbital Angular Momentum Holography, Nat. Commun. source
    • cites [44] Fang, 2020, Orbital Angular Momentum Holography for High-Security Encryption, Nat. Photonics source
    • cites [45] Ren, 2016, On-Chip Noninterference Angular Momentum Multiplexing of Broadband Light, Science source
  • Findingreasoning

    Illuminating the metasurface with a vortex beam carrying the exact designed topological charge reconstructs the target hologram because of OAM selectivity.

    “By illuminating the same metasurface with a vortex beam carrying the exact topological charge as designed, the target hologram can be reconstructed due to the OAM selectivity.”
    Quote in the paperSubstantial claim
  • Findingown data

    The authors demonstrate OAM and polarization selective holography for information encryption and image generation using all-dielectric birefringent metasurfaces.

    “Here, we propose and demonstrate OAM and polarization selective holography for information encryption and image generation using all-dielectric birefringent metasurfaces.”
    Quote in the paperSubstantial claim
  • Findingnone given

    The authors demonstrate orbital angular momentum multiplexing at different polarization channels using a birefringent metasurface for holographic encryption.

    “Here, we propose and demonstrate orbital angular momentum multiplexing at different polarization channels using a birefringent metasurface for holographic encryption.”
    Quote in the paperSubstantial claim
  • Findingnone given

    A vortex array in the orthogonal polarization channel serves as an indicator of the angular momentum carried by the input beam.

    “Besides, we realize a vortex array in the orthogonal polarization channel as the indicator of the angular momentum carried out by the input beam.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim. 10
  • It may state two separate claims as one. 20

  • Probably not a substantial claim.

    Premisecitation

    Metasurfaces can tailor electromagnetic wavefronts through two-dimensional arrays of nanoscale antennas or resonators.

    “Metasurfaces can provide versatile platforms to tailor an electromagnetic wavefront by designing two-dimensional arrays of nanoscale antennas or resonators.”
    Quote in the paperSubstantial claim2 of 8 sources checked
    • cites [3] Yu, 2012, A Broadband, Background-Free Quarter-Wave Plate Based on Plasmonic Metasurfaces, Nano Lett. source
    • cites [4] Lin, 2014, Dielectric Gradient Metasurface Optical Elements, Science source
    • cites [5] Kildishev, 2013, Planar Photonics with Metasurfaces, Science source
    • cites [6] Liu, 2014, Broadband Metasurfaces with Simultaneous Control of Phase and Amplitude, Adv. Mater. source
    • cites [7] Cui, 2014, Coding Metamaterials, Digital Metamaterials and Programmable Metamaterials, Light: Sci. Appl. source

      The 1-bit coding metamaterials section (p. 3) describes a two-dimensional metasurface array whose elements control the directions of reflected electromagnetic waves. But the paper’s demonstrated elements are millimeter-scale metallic structures (Digital metamaterials, p. 6), not nanoscale antennas or resonators, so it does not support that part of the claim. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [8] Yang, 2014, Dielectric Meta-Reflectarray for Broadband Linear Polarization Conversion and Optical Vortex Generation, Nano Lett. source
    • cites [9] Aieta, 2015, Multiwavelength Achromatic Metasurfaces by Dispersive Phase Compensation, Science source
    • cites [10] Jiang, 2019, When Metasurface Meets Hologram: Principle and Advances, Adv. Opt. Photonics source

  • It may state two separate claims as one.

    Premisecitation

    Metasurface holography can overcome traditional holography challenges and offers a large field of view, removal of unwanted diffraction orders, and high information capacity.

    “Especially, metasurface holography can conquer the challenges faced by traditional holography and possesses the advantages of a large field of view, elimination of unwanted diffraction orders, and high information capacity.”
    Quote in the paperSubstantial claim4 of 4 sources checked
    • cites [21] Wen, 2015, Helicity Multiplexed Broadband Metasurface Holograms, Nat. Commun. source

      The Conclusion (page unavailable) reports a wide field of view and says the device addresses image quality, efficiency, and bandwidth challenges of polarization-multiplexed holograms. The Results—Design section (page unavailable) says its off-axis design avoids overlap with the zero-order spot, not that it eliminates unwanted diffraction orders. The copy describes multiplexing two images but does not establish the claimed high information capacity. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [22] Ni, 2013, Metasurface Holograms for Visible Light, Nat. Commun. source

      The Results (p. 4) state that no energy goes to higher-order diffraction, supporting the claim about unwanted diffraction orders. The introduction (p. 2) says the hologram uses all its spatial bandwidth and addresses limitations of traditional holograms, but the cited passages do not establish a large field of view or explicitly demonstrate high information capacity. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [23] Zheng, 2015, Metasurface Holograms Reaching 80% Efficiency, Nat. Nanotechnol. source

      The paper’s concluding passage (page not supplied) reports a holographic image projected over a broad angular range and extremely low zeroth-order diffraction efficiency. These support the large-field-of-view idea and suppression of one unwanted diffraction order, but not elimination of all unwanted orders. The passages do not establish high information capacity or the broader claim that metasurface holography overcomes traditional holography’s challenges. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [24] Huang, 2013, Three-Dimensional Optical Holography Using a Plasmonic Metasurface, Nat. Commun. source

  • It may state two separate claims as one.

    Findingreasoning

    Using OAM beams to depict particular image detail while preserving useful aspects reveals hidden information as camouflage, giving a more sophisticated scene than plane wave illumination.

    “By utilizing OAM beams to depict particular image detail while preserving useful aspects of the images, some hidden information (camouflage) can be revealed, providing a more sophisticated scene than the plane wave illumination case.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    With Gaussian beam illumination, no image information appears in the Txx and Tyy channels, while an array of vortex beams with spatially variant topological charges appears in the cross-polarization Txy and Tyx channels.

    “When illuminating the metasurface with a Gaussian beam, no image information is observed in the Txx and Tyy channels (subscript ab denotes the input and output polarization channels), while an array of vortex beams with spatially variant topological charges can be observed in the cross-polarization Txy and Tyx channels.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    For l=40 or l=20, the words NATURE or SCIENCE appear in the copolarization channels, while the vortex array changes its spatial distribution in the cross-polarization channels as an indicator of the incident OAM.

    “For example, the word “NATURE” or “SCIENCE” shows up in the copolarization channels (with topological charge l = 40 or l = 20, respectively), while the vortex array changes its spatial distributions accordingly in the cross-polarization channel (Txy and Tyx), serving as an indicator for the incident OAM.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper may give no reason why it holds.

    Findingnone given

    Ideally, there is no crosstalk between the different output polarization channels.

    “Ideally, there is no crosstalk between the different output polarization channels.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingown data

    Zero-order spots remain observable at the center of the holographic images because of fabrication inaccuracies and the discrete nature of the metasurface.

    “Note that the zero-order spots are still observable at the center of the holographic images due to fabrication inaccuracies as well as the discrete nature of the metasurface.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingnone given

    The authors propose and demonstrate several holographic encryption and display strategies using orbital angular momentum and multiple polarization selective channels.

    “In summary, we propose and demonstrate several holographic encryption and display strategies using orbital angular momentum and multiple polarization selective channels.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingreasoning

    Illuminating the sample with other OAM beams causes overlap of lower-intensity donuts, making the image blurry and hiding clear image formation.

    “Therefore, illuminating the sample with other OAM beams results in the overlap of lower intensity donuts that cause the image to be blurry and the clear image formation is hidden.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingown data

    In the experiment, a donut-shaped residual beam spot appears as a zero-order diffraction spot because of the discrete metasurface and fabrication deviation from the theoretical design.

    “Note that in the experiment, a beam spot (residual light) with donut shape appears as a zero-order diffraction spot due to the discrete nature of the metasurface and the deviation of the sample fabrication from the theoretical design.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    The PSNRs of the images NATURE and SCIENCE in Figure 3g,h are 29.11 and 29.83 dB, respectively.

    “The peak signal-to-noise ratios (PSNRs) of the images “NATURE” and “SCIENCE” in Figure 3g,h are 29.11 and 29.83 dB, respectively”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingreasoning

    The lower contrast for vortex beam illumination compared with plane wave illumination is due to the vortex beam's donut-shaped intensity distribution, so the metasurface efficiency is lower.

    “The lower contrast for the vortex beam illumination compared to that of the plane wave case is due to the fact that the vortex beam has a donut-shaped intensity distribution. Hence the efficiency of the metasurface is lower.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingreasoning

    When the meta-holograms are illuminated with polarized light carrying the opposite OAM, the encoded phases are quenched and the output field has the required phase, while unmatched OAM values produce blurry reconstructed images.

    “As mentioned above, when the meta-holograms are illuminated with polarized light carrying the opposite OAM, the corresponding encoded phases (l1, l2, or l3) are “quenched” and the output light field possesses the required phase of φxx, φxy (or φyx), and φyy, while on the other hand for unmatched OAM values the reconstructed images become blurry.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingreasoning

    OAM selective holography, optical OAM indicators, and optical camouflage by depicting sophisticated detailed information are realized within a single metasurface by choosing different input-output polarization channels.

    “OAM selective holography together with optical OAM indicators and optical camouflage by depicting sophisticated detailed information are realized within a single metasurface by choosing different input/output polarization channels.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingreasoning

    Illumination with either a plane wave or a vortex beam reconstructs vivid holographic images, but only incident light carrying the designed OAM reveals sophisticated details.

    “Hence, by illuminating either by the plane wave or the vortex beam, vivid holographic images can be reconstructed. However, only the incident light carrying the designed OAM can reveal some sophisticated details.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    Under Gaussian beam illumination, the Tyy channel reconstructs a filled leaf; when l=40 is carried by the incident beam, a sawtooth shape appears at the edge of the filled leaf, demonstrating a serrated leaf.

    “In addition, the Tyy polarization channel shows the reconstruction of a filled leaf for the Gaussian beam illumination (Figure 4e,g). Again, when l = 40 is carried by the incident beam, a sawtooth shape appears at the edge of the filled leaf, which demonstrates a serrated leaf in Figure 4f,h.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    For an incident plane wave with l=0, image information is hidden in the Txx and Tyy channels; for l=40 with x polarization or l=20 with y polarization, the desired images NATURE and SCIENCE are reconstructed in Txx and Tyy, respectively.

    “For an incident plane wave with l = 0, the reconstructed image information is hidden in the Txx, Tyy channels (Figure 3a–d), while for the illuminating light carrying the specific OAM (l = 40 with x polarization or l = 20 with y polarization illumination) the desired images of “NATURE” and “SCIENCE” are reconstructed in the Txx, Tyy channels, respectively (Figure 3e–h).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    Under Gaussian beam illumination, the Txx channel reconstructs the image of grapes; when the incident light carries l=40 with x polarization, the grapes show additional detailed textures.

    “For the Gaussian beam illumination, the Txx channel reconstructs the image of the grapes (as shown in Figure 4a,c). When the incident light carries a topological charge of l = 40 with x polarization, the grapes show some additional detailed textures (Figure 4b,d).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Interpretationnone given

    The technique can be applied to beam shaping, optical camouflage, data storage, and dynamic displays.

    “Such a technique can be applied for beam shaping, optical camouflage, data storage, and dynamic displays.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. It may be too vague to check against evidence. It may state two separate claims as one.

    Interpretationreasoning

    Greater OAM mode selectivity for optical holography may provide higher flexibility in optical encryption, larger data storage capacity, and innovation in dynamic displays.

    “A larger OAM mode selectivity for optical holography may provide higher flexibility in optical encryption, larger data storage capacity, and innovation in dynamic displays.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. It may state two separate claims as one.

    Premisecitation

    Vortex beams carrying OAM have a donut-shaped intensity distribution and helical phase factors exp(ilφ), where l is the topological charge and φ is the azimuthal angle.

    “Vortex beams that carry OAM modes are characterized by a donut-shaped intensity distribution and exhibit helical phase factors exp(ilφ), where l indicates the topological charge number and φ is the azimuthal angle.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [25] Zhao, 2018, Demonstration of Orbital Angular Momentum Multiplexing and Demultiplexing Based on a Metasurface in the Terahertz Band, ACS Photonics source

  • Probably not a substantial claim.

    Premisenone given

    The polarization selectivity of the metasurface depends on its birefringent response to incident light.

    “The polarization selectivity of such a metasurface relies on the birefringent response to the incident light.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    With orthogonality of multiple OAM states, any possible OAM combination can be optimized for the same polarization channel, and the incident OAM beam acts as a key to unlock specific information.

    “With the help of the orthogonality of multiple OAM states, any possible OAM combination can be optimized for the same polarization channel, whereas the incident OAM beam works like a key to unlock the specific information.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. It may be too vague to check against evidence. It may state two separate claims as one.

    Interpretationreasoning

    The method enhances information capacity and enriches potential applications in encryption and display technologies.

    “Such a method further enhances the information capacity and enriches the potential applications in encryption and display technologies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim.

    Interpretationreasoning

    Using OAM selectivity and polarization channel combinations, including circular polarization channels, several possibilities exist for information encryption and decryption.

    “Using the advantage of the OAM selectivity and the polarization channel combinations, including the circular polarization channels, several possibilities for applications exist in encryption and decryption of information (see Supporting Information).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationown data

    The OAM input beam acts like an eraser, producing an effect similar to image depletion and reshaping image information to reveal more details.

    “In this case, the OAM input beam works like an eraser, which can realize an effect like image depletion and therefore a reshaping of the image information (e.g., revealing more details of the image).”
    Quote in the paperSubstantial claim
26 of 26

  • The paper relies on this without support.

    The orbital angular momentum of a light beam can be treated as an additional degree of freedom.

    “Despite the well-known light parameters, such as amplitude, phase, polarization, and frequency, the orbital angular momentum (OAM) of a beam can be regarded as another degree of freedom.”

  • The authors state this as an assumption.

    Near-field coupling between adjacent nanofins is negligible.

    “Note that the near-field coupling between neighboring nanofins is negligible.”

  • The paper relies on this without support.

    The main problems in OAM selective holography are sparse sampling and the need for postprocessing to remove crosstalk between images.

    “However, the major problems are the sparse sampling and the requirement of postprocessing to eliminate crosstalk between the images.”

  • The paper relies on this without support.

    Angular momentum conservation governs the relationship between the input topological charge and the vortex array in the metasurface hologram.

    “According to the angular momentum conservation law, when the input beam carries a topological charge of b, the vortex array obeys l = m × lx + b.”
4 of 4

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Conclusion combines results from two metasurfaces into one

    Minor

    The conclusion says the OAM-selective hologram, OAM indicators, and optical camouflage were realized within a single metasurface. The results instead introduce another metasurface sample for the camouflage demonstration.

1 of 1

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Metadata

Authors
Zhou, H., Sain, B., Wang, Y., Schlickriede, C., Zhao, R., Zhang, X., Wei, Q., Li, X., Huang, L., & Zentgraf, T.
Affiliations
  • Beijing Institute of Technology (CN)
  • Paderborn University (DE)
  • Beijing Institute of Technology , , ,
Corresponding author
  • Wang, Yongtian
  • Huang, Lingling
  • Zentgraf, Thomas
ORCID
Venue
ACS Nano
Publisher
American Chemical Society (ACS)
Published
2020-04-29
Volume
14
Issue
5
Pages
5553-5559
ISSN
  • 1936-0851 (ISSN-L)
  • 1936-086X
DOI
10.1021/acsnano.9b09814
PMC
PMC7254835
OpenAlex
W3019251339
Cited by
301
References
54
Citations by year
2026: 41 · 2025: 54 · 2024: 63 · 2023: 60 · 2022: 47 · 2021: 32 · 2020: 4
FWCI
24.64
Type
journal article
Language
en
Open access
Licence
Locations
  • ACS Nano (publishedVersion, other-oa)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • arXiv (Cornell University)
Funders
  • H2020 European Research Council (724306)
  • Deutsche Forschungsgemeinschaft (ZE953/11-1)
  • National Natural Science Foundation of China (61775019, 61861136010)
  • Ministry of Science and Technology of the People's Republic of China (2017YFB1002900)
  • Fok Ying Tong Education Foundation (161009)
  • Natural Science Foundation of Beijing Municipality (4172057)
  • Beijing Nova Program (Z171100001117047)
  • Beijing Outstanding Young Scientist Program (BJJWZYJH01201910007022)
Topics
  • Physical Sciences › Materials Science › Electronic, Optical and Magnetic Materials › Metamaterials and Metasurfaces Applications
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Orbital Angular Momentum in Optics
  • Physical Sciences › Engineering › Media Technology › Advanced Optical Imaging Technologies
Keywords
metasurface holography, orbital angular momentum, polarization multiplexing, holographic encryption, topological charge, super-resolution, optical camouflage, data storage, dynamic displays, beam shaping

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