Nematic twist angle due to the Casimir-Lifshitz torque from cholesteric liquid crystals

We theoretically explore the chirality-dependent Casimir-Lifshitz torque between nematic and cholesteric 5CB liquid crystals across nanometer-scale silica gaps ranging from 10 to 100 nm thick. Through the spiral staircase model, our calculations reveal that the angular position of the torque maximum varies with separation distance, accompanied by significant nematic twist angles (of up to 24°). We conclude that, under the conditions studied, it is possible to experimentally test the results of the spiral staircase model via the method introduced by Somers et al. (<ns0:sc>Somers</ns0:sc> D. A. T. et al., Nature, 564 (2018) 386).