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arXiv · 2004.13704

Orientational correlations in active and passive nematic defects

D. J. G. Pearce·J. Nambisan·P. W. Ellis·A. Fernandez-Nieves·L. Giomi
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Abstract

We investigate the emergence of orientational order among +1/2 disclinations in active nematic liquid crystals. Using a combination of theoretical and experimental methods, we show that +1/2 disclinations have short-range antiferromagnetic alignment, as a consequence of the elastic torques originating from their polar structure. The presence of intermediate -1/2 disclinations, however, turns this interaction from anti-aligning to aligning at scales that are smaller than the typical distance between like-sign defects. No long-range orientational order is observed. Strikingly, these effects are insensitive to material properties and qualitatively similar to what is found for defects in passive nematic liquid crystals.

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D. J. G. Pearce, J. Nambisan, P. W. Ellis, A. Fernandez-Nieves, L. Giomi. 2021-11-05. Orientational correlations in active and passive nematic defects. https://doi.org/10.1103/physrevlett.127.197801

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