Gapless Phason in an Antiferroelectric Liquid Crystal
| Autor: | Theo Rasing, M.M. Wittebrood, Hiroshi Orihara, Igor Muševič, Martin Čopič, Bostjan Zeks, Y. Ishibashi, Robert Blinc |
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| Rok vydání: | 1993 |
| Předmět: |
Physics
Condensed matter physics Liquid crystals Scanning Probe Microscopy Spontaneous symmetry breaking Rotational symmetry General Physics and Astronomy Phason dispersion Symmetry (physics) Explicit symmetry breaking Gapless playback Liquid crystal Spectroscopy of Solids and Interfaces Phase (matter) Commensurate-incommensurate transformations Phason GeneralLiterature_REFERENCE(e.g. dictionaries encyclopedias glossaries) |
| Zdroj: | Physical Review Letters, 71, 1180-1183 Physical Review Letters, 71, 8, pp. 1180-1183 |
| ISSN: | 0031-9007 |
| Popis: | The dynamics of liquid crystals is in certain respects richer than the dynamics of 3D periodic solids. In con trast to these systems, many liquid crystalline phases ex hibit a continuous rotational symmetry, which can be broken at the transition to phases of lower symmetry. This should allow for the existence of symmetry recover ing, zero frequency Goldstone modes, which are known to occur in particle physics and incommensurate systems. A particularly interesting Goldstone model, which is the subject of this study, should exist in antiferroelectric liquid crystals. of the high temperature phase. In the antiferroelectric Sm-CA' phase, the phason mode represents the sliding, or what is equivalent, the slow rotation of the double twisted helicoidal modulation wave, restoring the symmetry, lost at the Sm-A- Sm-CA' transition. Since the Sm-A * phase has the continuous Dco symmetry, whereas the symmetry of the Sm-CA' phase is discrete, the symmetry recovering phason is here predicted to be a truly gapless Goldstone mode. |
| Databáze: | OpenAIRE |
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