Emergence of hexatic and long-range herringbone order in two-dimensional smectic liquid crystals : A Monte Carlo study

TL;DR

This study uses Monte Carlo simulations to explore the critical behavior of a coupled XY model with hexatic and herringbone orderings in two-dimensional smectic liquid crystals, revealing novel continuous phase transitions.

Contribution

It introduces a high-resolution Monte Carlo approach to analyze coupled hexatic and herringbone fields, uncovering new continuous transition phenomena in 2D liquid crystals.

Findings

Both long-range hexatic and herringbone orders can emerge simultaneously.

Specific-heat exponents match experimental data near smecticA-hexaticB transition.

Discovery of novel continuous phase transitions in the model.

Abstract

Using a high resolution Monte Carlo simulation technique based on multi-histogram method and cluster-algorithm, we have investigated critical properties of a coupled XY model, consists of a six-fold symmetric hexatic and a three-fold symmetric herringbone field, in two dimensions. The simulation results demonstrate a series of novel continues transitions, in which both long-range hexatic and herringbone orderings are established simultaneously. It is found that the specific-heat anomaly exponents for some regions in coupling constants space are in excellent agreement with the experimentally measured exponents extracted from heat-capacity data near the smecticA-hexaticB transition of two-layer free standing films