Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Optical isotropy and iridescence in a smectic ‘blue phase’

Abstract

When liquid crystal molecules are chiral, the twisted structure competes with spatially uniform liquid crystalline orders, resulting in a variety of modulated liquid crystal phases, such as the cholesteric blue phase1, twist grain boundary2,3,4 and smectic blue phases5. Here we report a liquid crystal smectic blue phase (SmBPiso), formed from a two-component mixture containing a chiral monomer and a ‘twin’ containing two repeat units of the first molecule connected by a linear hydrocarbon spacer. The phase exhibits the simultaneous presence of finite local-order parameters of helices and smectic layers, without any discontinuity on a mesoscopic length scale. The anomalous softening of elasticity due to a strong reduction in entropy caused by mixing the monomer and the twin permits the seamless coexistence of these two competing liquid crystal orders. The new phase spontaneously exhibits an optically isotropic but uniformly iridescent colour and automatically acquires spherical symmetry, so that the associated photonic band gap6,7,8,9 maintains the same symmetry despite the local liquid crystalline order. We expect a range of unusual optical transmission properties based on this three-dimensional isotropic structure, and complete tunability due to the intrinsic softness and responsiveness of the liquid crystalline order against external fields.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Phase diagram for the twin/monomer mixture.
Figure 2: Polarizing microscope photographs in SmBPs.
Figure 3: Macroscopic and microscopic structural analysis in SmBPs.
Figure 4: Mechanical properties in SmBPs.

Similar content being viewed by others

References

  1. Ketzerow, H. S. & Bahr, C. (eds) Chirality in Liquid Crystals 186–222 (Springer, New York, 2002)

  2. Renn, S. R. & Lubensky, T. C. Abrikosov dislocation lattice in a model of the cholesteric-to-smectic A transition. Phys. Rev. A. 38, 2132–2147 (1988)

    Article  ADS  CAS  Google Scholar 

  3. Goodby, J. W. et al. Characterization of a new helical smectic liquid crystal. Nature 337, 449–452 (1989)

    Article  ADS  CAS  Google Scholar 

  4. Dierking, I. & Lagerwall, S. T. A review of textures of TGB* phase under different anchoring conditions. Liq. Cryst. 26, 83–95 (1999)

    Article  CAS  Google Scholar 

  5. Pansu, B., Grelet, E., Li, M. H. & Nguyen, H. T. Hexagonal symmetry for smectic blue phases. Phys. Rev. E 62, 658–665 (2000)

    Article  ADS  CAS  Google Scholar 

  6. John, S. Electromagnetic absorption in a disordered medium near photon mobility edge. Phys. Rev. Lett. 53, 2169–2172 (1984)

    Article  ADS  Google Scholar 

  7. Yablonovitch, E. Inhibited spontaneous emission in solid-state physics and electronics. Phys. Rev. Lett. 58, 2059–2062 (1987)

    Article  ADS  CAS  Google Scholar 

  8. John, S. Strong localization of photons in certain disordered dielectric superlattices. Phys. Rev. Lett. 58, 2486–2489 (1987)

    Article  ADS  CAS  Google Scholar 

  9. Busch, K. & John, S. Liquid-crystal photonic-band-gap materials: the tunable electromagnetic vacuum. Phys. Rev. Lett. 83, 967–970 (1999)

    Article  ADS  CAS  Google Scholar 

  10. Nishiyama, I., Yamamoto, J., Goodby, J. W. & Yokoyama, H. Symmetric chiral liquid crystalline twin exhibiting stable ferroelectric and antiferroelectric phases and a chirality-induced isotropic-isotropic liquid transition. J. Mater. Chem. 11, 2690–2693 (2001)

    Article  CAS  Google Scholar 

  11. Yamamoto, J. & Okano, K. Anomalous hydrodynamic behaviors of smectic liquid crystals at low frequencies. Jpn. J. Appl. Phys. 30, 754–763 (1991)

    Article  ADS  CAS  Google Scholar 

  12. DiDonna, B. A. & Kamien, R. D. Smectic phases with cubic symmetry: the splay analog of the blue phase. Phys. Rev. Lett. 89, 215504 (2002)

    Article  ADS  CAS  Google Scholar 

  13. Yamamoto, J. & Tanaka, H. Transparent nematic phase in liquid-crystal based microemulsion. Nature 409, 321–325 (2001)

    Article  ADS  CAS  Google Scholar 

  14. MacKintosh, F. C. & Lubensky, T. C. Orientational order, topology, and vesicle shapes. Phys. Rev. Lett. 67, 1169–1173 (1991)

    Article  ADS  MathSciNet  CAS  Google Scholar 

  15. Zhong-can, O. & Ji-xing, L. Helical structure of tilted chiral lipid bilayers viewed as cholesteric liquid crystals. Phys. Rev. Lett. 65, 1679–1682 (1990)

    Article  ADS  CAS  Google Scholar 

  16. Niori, T., Sekine, T., Watanabe, J., Furukawa, T. & Takezoe, H. Distinct ferroelectric smectic liquid crystals consisting of banana shaped achiral molecules. J. Mater. Chem. 6, 1231–1233 (1996)

    Article  CAS  Google Scholar 

  17. Thisayukta, J., Takezoe, H. & Watanabe, J. Study on helical structure of the B4 phase formed from achiral banana-shaped molecules. Jpn. J. Appl. Phys. 40, 3277–3287 (2001)

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

We thank L. Hough and N. A. Clark for suggesting methods of preparing the frozen replica of the TEM observation.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Jun Yamamoto.

Ethics declarations

Competing interests

Reprints and permissions information is available at npg.nature.com/reprintsandpermissions. The authors declare no competing financial interests.

Supplementary information

Supplementary Figure S1

A freeze-fracture replica of the TEM photograph of a fractured SmBPIso. The scale bar corresponds to 1 µm. We would like to emphasize that the fractured surface profile represents the spatial distribution of the layers since they can be fractured easily along the plane of the layers. (JPG 130 kb)

Supplementary Figure S2

A magnified photograph of Supplementary Fig. S1. The scale bar corresponds to 200 nm. The thin string-like pattern indicates that the interconnected structure was formed by the multi-layer bundle. (JPG 122 kb)

Supplementary Figure S3

A frozen replica of the TEM photograph of the free air interface of SmBPIso. The scale bar corresponds to 1 µm. The surface step of the smectic layer curved automatically and formed a wavy structure due to the bulk of the multi-lamellar interconnected structure. (JPG 128 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Yamamoto, J., Nishiyama, I., Inoue, M. et al. Optical isotropy and iridescence in a smectic ‘blue phase’. Nature 437, 525–528 (2005). https://doi.org/10.1038/nature04034

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature04034

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing