title: Investigations of nanoscale helical pitch in smectic-C*alpha and smectic-C* phases of a chiral smectic liquid crystal using differential optical reflectivity measurements.
abstract: Differential optical reflectivity (DOR) was used to study the temperature dependence of the short helical pitch in freestanding films of a liquid crystal compound. The experimentally measured DOR signal was fitted using Berreman's 4 x 4 matrix method to get the pitch value in the smectic-C*alpha (sMC*alpha) phase. The results show continuous evolution of the pitch between the smectic-C*alpha and sMC*alpha phases. In sMC*alpha, the pitch decreases as temperature increases and is found to level off at 16+/-1 smectic layers at the sMC*alpha to smectic-A* transition.
authors.affiliation: Department of Electronic and Electrical Engineering, Trinity College, University of Dublin, Dublin 2, Ireland.
authors.forename: V P
authors.initials: VP
authors.lastname: Panov
authors.forename: B K
authors.initials: BK
authors.lastname: McCoy
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Liu
authors.forename: J K
authors.initials: JK
authors.lastname: Vij
authors.forename: J W
authors.initials: JW
authors.lastname: Goodby
authors.forename: C C
authors.initials: CC
authors.lastname: Huang