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External-field-induced tricritical point in a fluctuation-driven nematic-smectic-A transition

Ranjan Mukhopadhyay·Anand Yethiraj·John Bechhoefer
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Abstract

We study theoretically the effect of an external field on the nematic-smectic-A (NA) transition close to the tricritical point, where fluctuation effects govern the qualitative behavior of the transition. An external field suppresses nematic director fluctuations, by making them massive. For a fluctuation-driven first-order transition, we show that an external field can drive the transition second-order. In an appropriate liquid crystal system, we predict the required magnetic field to be of order 10 T. The equivalent electric field is of order $1 V/μm$.

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Ranjan Mukhopadhyay, Anand Yethiraj, John Bechhoefer. 1999-06-27. External-field-induced tricritical point in a fluctuation-driven nematic-smectic-A transition. https://doi.org/10.1103/physrevlett.83.4796

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