Liquid crystal surface alignments by using ion beam sputtered magnetic thin films

Abstract

A method for liquid crystal surface alignment by using a one-step, ion beam bombardment of the glass substrates is demonstrated. Precoating by polyimide is not necessary. The authors show that the homeotropic alignment is achieved due to orientation of the diamagnetic nematogenic molecules by the magnetic field from the gamma-Fe2O3 ferrimagnetic thin films created on the substrates by ion beam bombardment. The film exhibits a high Curie temperature well above 300 K and a compensation temperature which is the typical feature of ferrimagnetism. This is a simple, noncontact, and reliable alignment method for liquid crystal devices. (C) 2007 American Institute of Physics.