Flexoelectricity-driven softening of bend elasticity leads to spontaneous chiral symmetry breaking in a polar fluid

Aitor Erkoreka; Josu Martinez-Perdiguero; Luka Cmok; Ema Hanžel; Jordan Hobbs; Calum J. Gibb; Richard J. Mandle; Nerea Sebastián; Alenka Mertelj

arXiv · 2602.15687

Flexoelectricity-driven softening of bend elasticity leads to spontaneous chiral symmetry breaking in a polar fluid

Aitor Erkoreka·Josu Martinez-Perdiguero·Luka Cmok·Ema Hanžel·Jordan Hobbs·Calum J. Gibb·Richard J. Mandle·Nerea Sebastián·Alenka Mertelj

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Abstract

The origin of recently observed spontaneous chiral symmetry breaking in polar fluids is an unsolved problem, and poses fundamental questions as to how heliconical structures emerge in systems composed of achiral molecules. We report on the softening of bend elasticity close to such phase transition, showing that flexoelectric coupling between the electric polarization and the bend deformation is the responsible mechanism, presumably arising from the bent shape of the constituent highly polar molecules.

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Aitor Erkoreka, Josu Martinez-Perdiguero, Luka Cmok, Ema Hanžel, Jordan Hobbs, Calum J. Gibb, Richard J. Mandle, Nerea Sebastián, Alenka Mertelj. 2026-02-17. Flexoelectricity-driven softening of bend elasticity leads to spontaneous chiral symmetry breaking in a polar fluid. https://arxiv.org/abs/2602.15687

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