title: Light modulation in planar aligned short-pitch deformed-helix ferroelectric liquid crystals.
abstract: We study both experimentally and theoretically modulation of light in a planar aligned deformed-helix ferroelectric liquid crystal (DHFLC) cell with subwavelength helix pitch, which is also known as a short-pitch DHFLC. In our experiments, the azimuthal angle of the in-plane optical axis and electrically controlled parts of the principal in-plane refractive indices are measured as a function of voltage applied across the cell. Theoretical results giving the effective optical tensor of a short-pitch DHFLC expressed in terms of the smectic tilt angle and the refractive indices of the ferroelectric liquid crystal (FLC) are used to fit the experimental data. The optical anisotropy of the FLC material is found to be weakly biaxial. For both the transmissive and reflective modes, the results of fitting are applied to model the phase and amplitude modulation of light in the DHFLC cell. We demonstrate that if the thickness of the DHFLC layer is about 50μm, the detrimental effect of field-induced rotation of the in-plane optical axes on the characteristics of an axicon designed using the DHFLC spatial light modulator in the reflective mode is negligible.
authors.affiliation: Lebedev Physical Institute, Leninsky Prospekt 53, 119991 Moscow, Russia.|Samara State Aerospace University, Moskovskoe Shosse 34, 443086 Samara, Russia.
authors.forename: Svetlana P
authors.initials: SP
authors.lastname: Kotova
authors.affiliation: Lebedev Physical Institute, Leninsky Prospekt 53, 119991 Moscow, Russia.
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Samagin
authors.affiliation: Lebedev Physical Institute, Leninsky Prospekt 53, 119991 Moscow, Russia.|Hong Kong University of Science and Technology, Clear Water Bay, 999077 Kowloon, Hong Kong.
authors.forename: Evgeny P
authors.initials: EP
authors.lastname: Pozhidaev
authors.affiliation: Hong Kong University of Science and Technology, Clear Water Bay, 999077 Kowloon, Hong Kong.|Saint Petersburg National Research University of Information Technologies, Mechanics and Optics, Kronverskyi Prospekt 49, 197101 St. Petersburg, Russia.
authors.forename: Alexei D
authors.initials: AD
authors.lastname: Kiselev