Flexoelectric Induced Vanishing of the Cholesteric Helix

References

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• Although the PM model predicts 1 for the ratio of the optic axis tilt to a dimensionless field whereas the bulk effect predicts 1/, this is too fine a difference to distinguish between the two models. Measured values for the flexoelectric coefficient, e, differ by nearly a factor of 10. The factor gives an e = 5 × 10−5cgs in plane of e = 3.5 × 10−5 cgs using their slope data and values they take for the material constants K and q [3]. Taking K = K1 = K3 ∼ 5 × 10−7 dynes, e is about one half smaller than the above estimates from the slope data
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