Chiral plasmonic nanostructures fabricated with circularly polarized light

Abstract

Chiral plasmonic nanostructures (cPNSs) have garnered extensive interest across disciplines due to their strong interaction with circularly polarized light (CPL). Numerous fundamental studies have demonstrated the enhancement of chiroptic effects in molecular systems and quantum emitters facilitated by chiral metal nanostructures; for example, the detection of DNA at attomolar concentrations has been achieved using cPNSs. In recent years, significant advancements have been made in the colloidal synthesis of chiral plasmonic nanostructures. A noteworthy breakthrough involves the use of CPL to fabricate cPNSs. As a traceless chiral agent, CPL holds great potential for integration with nanofabrication technologies. In this review, we will summarize the progress made in fabricating cPNSs using CPL. We will discuss the mechanisms involved in the CPL-based fabrication process and share our insights regarding the outstanding questions related to cPNSs produced by CPL. Additionally, we will outline common techniques for characterizing the chiroptic effects of cPNSs in both the far field and the near field. Last, we will review the various applications of cPNSs and highlight the most promising applications of cPNSs fabricated using CPL.

Keywords: circular dichroism; circularly polarized light; plasmonic nanocrystals.

Figure 1

Representative cPNSs. (a) Atomic force microscopy (AFM) image of chiral gold propellers (top) and scanning electron microscopy (SEM) image of gold helices. (bottom) (b) A schematic of complex cPNSs constructed by glancing angle deposition and their transmission electron microscopy (TEM) image. (c) Top: Schematics and TEM images of pyramidal assemblies of gold NCs of different sizes. Bottom: TEM image of gold NC double helix. (d) Schematics (left) and SEM images (right) of gold helicoids obtained with glutathione. (e) Low-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) image of chiral gold nanorods (AuNRs) obtained with cosurfactant (R)-BINAMINE. Scale bar is 100 nm. (f) Schematics (top) and SEM images (bottom) of chiral AuNR/PbO₂ nanostructures obtained with CPL. Figure 1, panel (a) top is adapted with permission from [26] © Optical Society of America. This content is not subject to CC BY 4.0. Figure 1, panel (a) bottom was reproduced from [27] J. K. Gansel et al., Science, https://doi.org/10.1126%2Fscience.1177031%2C © 2009, AAAS. This content is not subject to CC BY 4.0. Figure 1, panel (b) was adapted from [28], (A. G. Mark et al., “Hybrid nanocolloids with programmed three-dimensional shape and material composition”, Nature Materials, Vol. 12, pages 802–807, published by Springer Nature, reproduced with permission from SNCSC). This content is not subject to CC BY 4.0. Figure 1, panel (c) top was adapted from [48], Copyright © 2009 American Chemical Society. This content is not subject to CC BY 4.0. Figure 1, panel (c) bottom was adapted from [38], Copyright © 2008 American Chemical Society. This content is not subject to CC BY 4.0. Figure 1, panel (d) was adapted from [19], (H. E. Lee et al., “Amino-acid- and peptide-directed synthesis of chiral plasmonic gold nanoparticles”, Nature, Vol. 556, pages 360–365, published by Springer Nature, reproduced with permission from SNCSC). This content is not subject to CC BY 4.0. Figure 1, panel (e) was reproduced from [52] G. González-Rubio et al., Science, https://doi.org/10.1126%2Fscience.aba0980%2C © 2020, AAAS. This content is not subject to CC BY 4.0. Figure 1, panel (f) was adapted from [20], Copyright © 2018 American Chemical Society. This content is not subject to CC BY 4.0.

Figure 2

Mechanisms of plasmon-mediated chemical reactions under CPL (the polarization is arbitrary in the graph). The EM field enhancement, localized hot carrier generation, and local thermal field are depicted as the three main effects of surface plasmon excitation and relaxation, each occurring at a different time scale.

Figure 3

Representative chiral metal/semiconductor heterostructures fabricated by CPL. (a) SEM images and circular dichroism (CD) spectra of chiral AuNR/PbO₂ nanostructures. (b) SEM images of chiral Au nanocube/PbO₂ nanostructures. (c) SEM images of chiral Au triangular plate (AuTP)/PbO₂ nanostructures. Scale bars are 100 nm. (d) Left top: schematic of the photodeposition of PbO₂ to form chiral AuBP/PbO₂ from achiral precursors with CPL. Left middle: an energy diagram depicting the possible mechanism of Pb²⁺ oxidation by hot holes. Left bottom: CD spectra of chiral AuBP/PbO₂ fabricated with 488, 532, 561, and 660 nm CPL. Right panel: SEM images of chiral AuBP/PbO₂ constructed using 488, 532, and 660 nm CPL. (e) SEM images and simulated electric field enhancement profile of Au triangle prisms using 488, 532, and 660 nm CPL. Figure 3, panel (a) was adapted from [20], Copyright © 2018 American Chemical Society. This content is not subject to CC BY 4.0. Figure 3, panel (b) was adapted from [90], with the permission of AIP Publishing. This content is not subject to CC BY 4.0. Figure 3, panel (c) was adapted from [91], T. Homma et al. “Photofabrication of Chiral Plasmonic Nanostructure Arrays”, ChemNanoMat., with permission from John Wiley and Sons. Copyright © 2023 Wiley-VCH GmbH. This content is not subject to CC BY 4.0. Figure 3, panel (d) was adapted from [56], Copyright © 2024 American Chemical Society. This content is not subject to CC BY 4.0. Figure 3, panel (e) was adapted from [92], Copyright © 2025 American Chemical Society. This content is not subject to CC BY 4.0.

Figure 4

Representative metallic chiral nanostructures fabricated with CPL. (a) CD and TEM images of Au nanoparticles (NPs) produced by illuminating CPL on HAuCl₄ solutions. (b, c) CD and SEM images of chiral Ag NPs produced on a glass slide via CPL with (b) and without (c) achiral Ag triangle plates as seeds. (d) Differential CD scattering (CDS) and SEM images of chiral Au nanocubes via illuminating CPL on achiral Au nanocubes immobilized on glass. (e) Structural evolution of chiral AgNRs fabricated with CPL and surface engineering (top two rows). CD and SEM images of chiral AgNRs after CPL illumination for 60 min (bottom). All scale bars are 200 nm in panel (e). Figure 4, panel (a) was adapted from [57], Copyright © 2019 American Chemical Society. This content is not subject to CC BY 4.0. Figure 4, panels (b) and (c) were adapted from [58], with the permission of AIP Publishing. This content is not subject to CC BY 4.0. Figure 4, panel (d) was adapted from [59], (© 2024 S. Lee et al., Angewandte Chemie, International Edition published by Wiley-VCH GmbH, distributed under the terms of the Creative Commons Attribution 4.0 International License, https://creativecommons.org/licenses/by/4.0). Figure 4, panel (e) was adapted from [103], (© 2025 T. Qiao et al., Small published by Wiley-VCH GmbH, distributed under the terms of the Creative Commons Attribution 4.0 International License, https://creativecommons.org/licenses/by/4.0).

Figure 5

(a, b) Top: Atomic force microscopy (AFM) images of Au metamolecules with photosensitive azobenzene-containing polymer displaced under CPL. Bottom: electric field enhancement simulation of Au metamolecules under CPL. (c) SEM and AFM images showing the spiral polydivinylbenzene with the achiral Au@Ag nanoparticle in the middle after CPL illumination. Figure 5, panel (a) was adapted from [107], Copyright © 2020 American Chemical Society. This content is not subject to CC BY 4.0. Figure 5, panel (b) was adapted from [108], T. Aoudjit et al. “Photochemical Imaging of Near-Field and Dissymmetry Factor in Chiral Nanostructures”, Advanced Optical Materials, with permission from John Wiley and Sons. Copyright © 2023 Wiley-VCH GmbH. This content is not subject to CC BY 4.0. Figure 5, panel (c) was adapted from [109], (© 2024 H.-Y. Ahn et al., Published by American Chemical Society, distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, https://creativecommons.org/licenses/by-nc-nd/4.0/). This content is not subject to CC BY 4.0.

Figure 6

(a) Map of the differential hot electron excitation rate (ΔRate_HE(r)) between LCPL and RCPL incidence for a rectangular Au prism. (b) Simulated CD spectra of a gold twister and an anti-twister. (c) 3D map of the normalized optical chirality around a four-helix structure on resonance with a pitch of 100 nm. Figure 6, panel (a) was adapted from [75], (© 2021 L. V. Besteiro et al., Published by American Chemical Society, distributed under the terms of the Creative Commons Attribution 4.0 International License, https://creativecommons.org/licenses/by/4.0). Figure 6, panel (b) was adapted from [115], Copyright © 2012 American Chemical Society. This content is not subject to CC BY 4.0. Figure 6, panel (c) was adapted from [125], Copyright © 2014 American Chemical Society. This content is not subject to CC BY 4.0.

Figure 7

Schematics of the (a) ORD and (b) CD measurement principles. (c) An array of split rings manifests optical activity at the oblique incidence of light. Optical activity is detected when the plane of the array is tilted around the x-axis. Figure 7, panel (c) was adapted with permission from [64], Copyright © 2009 by the American Physical Society. This content is not subject to CC BY 4.0.

Figure 8

(a) Experimental scheme of near field polarimetry measurements using NSOM and the ellipticity angle image for a single gold nanorectangle irradiated with linearly polarized light (white arrow). (b) Experimental scheme of CPL detection using CL in an SEM and the circularly polarized CL intensity map on an achiral V-shaped Al nanoantenna at different detection wavelengths. (c) Energy-filtered EELS intensity images on a left-handed Au nanohelix. (d) Integrated PE signals around Au NRs under CPL at various wavelengths. (e) SEM images of Au spirals with varying pitch sizes and their PINEM maps under LCPL. Figure 8, panel (a) was adapted from [126], Copyright © 2018 American Chemical Society. This content is not subject to CC BY 4.0. Figure 8, panel (b) was adapted from [129], Copyright © 2018 American Chemical Society. This content is not subject to CC BY 4.0. Figure 8, panel (c) was adapted from [132], (© 2023 R. Lingstädt et al., Published by American Chemical Society, distributed under the terms of the Creative Commons Attribution 4.0 International License, https://creativecommons.org/licenses/by/4.0). Figure 8, panel (d) was adapted from [72], (© 2021 T. Oshikiri et al., Published by American Chemical Society, distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, https://creativecommons.org/licenses/by-nc-nd/4.0/). This content is not subject to CC BY 4.0. Figure 8, panel (e) was adapted from [135], T. R. Harvey et al., “Probing Chirality with Inelastic Electron-Light Scattering”, Nano Letters, Copyright © 2020 American Chemical Society, distributed under the ACS AuthorChoice/Editors’ Choice via Creative Commons Attribution Non-Commercial No Derivative Works 4.0 Usage Agreement, https://pubs.acs.org/page/policy/authorchoice_ccbyncnd_termsofuse.html. This content is not subject to CC BY 4.0.

Figure 9

(a) Experimental and calculated transmittance spectra of LCPL (red) and RCPL (blue) measured with normal incidence on left-handed less-than-one-pitch helices (top), two pitches of left-handed helices (middle), and two pitches of right-handed helices (bottom). (b) Different images were reconstructed through a chiral metasurface depending on the polarization of the incident light. (c) Photocurrent maps of a metamaterial under CPL. Scale bars are 10 μm. Figure 9, panel (a) was reproduced from [27] J. K. Gansel et al., Science, https://doi.org/10.1126%2Fscience.1177031%2C © 2009, AAAS. This content is not subject to CC BY 4.0. Figure 9, panel (b) was adapted from [138], (© 2015 D. Wen et al., published by Springer Nature, distributed under the terms of the Creative Commons Attribution 4.0 International License, https://creativecommons.org/licenses/by/4.0). Figure 9, panel (c) was adapted from [141], (© 2015 W. Li et al., published by Springer Nature, distributed under the terms of the Creative Commons Attribution 4.0 International License, https://creativecommons.org/licenses/by/4.0).