Giant Magnetic Field-induced Phase Transitions in Dimeric Liquid Crystals.

ORAL

Abstract

Liquid crystals are responsive to external fields such as electric, magnetic fields. The first experimental observation of dependence of isotropic to nematic phase transition on the applied magnetic field was done using a strong magnetic field on bent-core nematogens and the phase transition temperature exhibited an upshift of 0.7 C at B$=$30 T [1]. We report on measurements of giant magnetic field-induced isotropic-nematic transition of chainsticks (nunchuks) type dimeric liquid crystals. Upon using the B$=$25 T split-helix resistive solenoid magnet at NHMFL, we have observed up to 18 C upshift of the isotropic to nematic phase transition temperature at B$=$22T. We discuss the results within the context of differential thermodynamic potential and the two basic mean-field theories. To our knowledge, this is the first observation of such huge shifts in the phase transitions of thermotropic liquid ctystals. [1] T. Ostapenko et al, Phys. Rev. Lett. 101, 247801 (2008).

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Authors

  • Seyyed Muhammad Salili

    Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA

  • Miroslaw Salamonczyk

    Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA

  • Maria-Gabriela Tamba

    Department of Nonlinear Phenomena, Institute for Experimental Physics, Otto von Guericke University Magdeburg, Magdeburg, Germany

  • Samuel Sprunt

    Department of Physics, Kent State University, Department of Physics, Kent State University, Kent, OH 44242, USA, Department of Physics,Kent State Univ - Kent

  • Georg Mehl

    Department of Chemistry, University of Hull, Hull HU6 7RX, UK

  • Antal Jakil

    Chemical Physics Interdisciplinary Program and Liquid Crystal Institute, Kent State University, Kent, OH 44242, Liquid Crystal Institute, Kent State University, Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA, Chemical Physics Interdisciplinary Program and Liquid Crystal Institute, Kent State Univ-Kent, Kent State University

  • James Gleeson

    Department of Physics, Kent State University, Department of Physics, Kent State University, Kent, OH 44242, USA, Department of Physics,Kent State Univ - Kent