How to Enhance Sensitivity of Liquid Crystals to External Magnetic Field?

• Authors: P. Kopčanský , N. Tomašovičová , V. Gdovinová , M. Timko , N. Éber , T. Tóth-Katona , J. Jadzyn , J. Honkonen , X. Chaud
• Languages of publication: EN

Abstracts

EN

Liquid crystals, due to their large dielectric anisotropy, respond very sensitively to application of an external electric field, whereas they are only weakly sensitive to the magnetic field. A possible way of improving that sensitivity is doping liquid crystals with magnetic nanoparticles. As a result, stable colloidal suspensions of liquid crystals with relatively low concentrations of magnetic nanoparticles (called ferronematics, ferrocholesterics, ferrosmectics, etc.) can be produced. We illustrate some examples of the influence of the magnetic field, as well as of a superposition of magnetic and electric fields on the structural transitions (e.g. on the Fréedericksz transition) in ferronematics based on the calamitic liquid crystal 4-(trans-4'-n-hexylcyclohexyl)-isothiocyanatobenzene (6CHBT). It is shown that the samples respond to the applied magnetic field of low strength. The effects of the magnetic particles and magnetic field on the nematic to isotropic phase transition temperature are discussed as well.

Keywords

EN

75.50.Mm; 61.30.Gd; 61.30.Hn

Discipline

• 61.30.Hn: Surface phenomena: alignment, anchoring, anchoring transitions, surface-induced layering, surface-induced ordering, wetting, prewetting transitions, and wetting transitions
• 61.30.Gd: Orientational order of liquid crystals; electric and magnetic field effects on order
• 75.50.Mm: Magnetic liquids

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2015
• Volume: 127
• Issue: 2
• Pages: 157-162

Dates

published

2015-02

Contributors

author

P. Kopčanský

• Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia

author

N. Tomašovičová

• Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia

author

V. Gdovinová

• Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia

author

M. Timko

• Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia

author

N. Éber

• Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, H-1525 Budapest, P.O. Box 49, Hungary

author

T. Tóth-Katona

• Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, H-1525 Budapest, P.O. Box 49, Hungary

author

J. Jadzyn

• Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60179 Poznan, Poland

author

J. Honkonen

• Department of Physical Sciences, University of Helsinki, Gustav Hällstromin katu 2, Helsinki, Finland

author

X. Chaud

• High Magnetic Field Laboratory, CNRS, 25 Avenue des Martyrs, Grenoble, France

References

• [1] P.G. de Gennes, The Physics of Liquid Crystals, Clarendon Press, Oxford 1974
• [2] V. Freedericksz, V. Zolina, Trans. Faraday. Soc. 29, 919 (1933), doi: 10.1039/TF9332900919
• [3] F. Brochard, P.G. de Gennes, J. Phys. (Paris) 31, 691 (1970), doi: 10.1051/jphys:01970003107069100
• [4] S.V. Burylov, Y.L. Raikher, J. Phys. Lett. A 149, 279 (1990), doi: 10.1016/0375-9601(90)90429-R
• [5] S.V. Burylov, Y.L. Raikher, J. Magn. Magn. Mater. 122, 62 (1993)
• [6] S.V. Burylov, Y.L. Raikher, Mol. Cryst. Liq. Cryst. 258, 107 (1995), doi: 10.1080/10587259508034552
• [7] R. Dabrowski, J. Dziaduszek, T. Szczucinski, Mol. Cryst. Liq. Cryst. Lett. 102, 155 (1984)
• [8] P. Kopčanský, N. Tomašovičová, M. Koneracká, V. Závišová, M. Timko, A. Džarová, A. Šprincová, N. Éber, K. Fodor-Csorba, T. Tóth-Katona, A. Vajda, J. Jadzyn, Phys. Rev. E 78, 011702 (2008), doi: 10.1103/PhysRevE.78.011702
• [9] N. Tomašovičová, P. Kopčanský, N. Éber, in: Anisotropy Research: New Developments, Ed. H.G. Lemu, Nova Sci. Publ., 2012
• [10] N. Podoliak, O.Buchnev, O. Buluy, G. D'Alessandro, M. Kaczmarek, Y. Reznikov, T.J. Sluckin, Soft Matter 7, 4742 (2011), doi: 10.1039/C1SM05051F
• [11] O. Buluy, S. Nepijko, V. Reshetnyak, E. Ouskova, V. Zadorozhnii, A. Leonhardt, M. Ritschel, G. Schönhense, Y. Reznikov, Soft Matter 7, 644 (2011), doi: 10.1039/C0SM00131G
• [12] N. Tomašovičová, M. Timko, Z. Mitróová, M. Koneracká, M. Rajňak, N. Éber, T. Tóth-Katona, X. Chaud, J. Jadzyn, P. Kopčanský, Phys. Rev. 87, 014501 (2013), doi: 10.1103/PhysRevE.87.014501
• [13] P. Kopčanský, N. Tomašovičová, T. Tóth-Katona, N. Éber, M. Timko, V. Zavišová, J. Majorošová, M. Rajňak, J. Jadzyn, X. Chaud, Magnetohydrodynamics 48, 407 (2012)
• [14] W. Helfrich, Phys. Rev. Lett. 24, 201 (1970), doi: 10.1103/PhysRevLett.24.201
• [15] I. Lelidis, G. Durand, Phys. Rev. E 48, 3822 (1993), doi: 10.1103/PhysRevE.48.3822
• [16] H. Stanley, Introduction to Phase Transitions and Critical Phenomena, Oxford Science, New York 1971
• [17] C. Rosenblatt, Phys. Rev. A 24, 2236 (1981)
• [18] T. Ostapenko, D.B. Wiant, S.N. Sprunt, A. Jákli, J.T. Gleeson, Phys. Rev. Lett. 101, 247801 (2008), doi: 10.1103/PhysRevLett.101.247801
• [19] P. Kopčanský, N. Tomašovičová, M. Koneracká, V. Zavišová, M. Timko, M. Hnatič, N. Éber, T. Tóth-Katona, J. Jadzyn, J. Honkonen, E. Beaugnon, X. Chaud, IEEE Trans. Magn. 47, 4409 (2011), doi: 10.1109/TMAG.2011.2160618
• [20] N. Tomašovičová, P. Kopčanský, M. Koneracká, L. Tomčo, V. Závišová, M. Timko, N. Éber, K. Fodor-Csorba, T. Tóth-Katona, A. Vajda, J. Jadzyn, J. Phys. Condens. Matter 20, 204126 (2008), doi: 10.1088/0953-8984/20/20/204123
• [21] P. Kedziora, J. Jadzyn, L. Hellemans, Phys. Rev. E 66, 021709 (2002), doi: 10.1103/PhysRevE.66.021709

Identifiers

DOI

10.12693/APhysPolA.127.157