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The electric field-induced modifications of magnetic anisotropy in CoFeB/MgO systems are studied using X-ray resonant magnetic scattering and magneto-optical Kerr effect. Voltage dependent changes of the magnetic anisotropy of −12.7 fJ/Vm and −8.32 fJ/Vm are observed for Ta/CoFeB/MgO and Hf/CoFeB/MgO systems, respectively. This implies that the interfacial perpendicular magnetic anisotropy is reduced (enhanced) when electron density is increased (decreased). X-ray resonant magnetic scattering measurements reveal that the small in-plane magnetic component of the remanent state of CoFeB/MgO systems with weak magnetic anisotropy changes depending on the applied voltage leading to modification of the magnetic anisotropy at the CoFeB/MgO interface.

Polyimide containing the chalcone moiety is expected to show the high photodimerization rate and stable alignment characteristics. We introduced the chalcone moiety as a side chain into the polyimide backbone to apply to the photo-alignment layer. The tilted angle of incident light produced out-of-the-plane orientation of chalcone side chain. The orientation effects align the LC in LCD, which possesses the various pretilt angles depending on the length of side chains.

The photoalignment of liquid crystal (LC) molecules located onto polyimide films with chalcone derivatives using linearly polarized UV (LPUV) light is investigated. The LPUV light irradiation generated dimerization products of the chalcones followed by isomerization of the chalcone derivatives. The alignment directions of LC molecules were either homeotropic or planar with respect to plane of polyimide film, depending upon the alkyl chain length attached on the chalcones.

We synthesized chalcone derivatives and introduced them as a side chain unit in the backbone of polyimide for photo-alignment layers. The rate of photoreaction was followed by the disappearance of the CCCO bond in the chalcone moiety using UV–visible spectroscopy. The absorption peak at around 340 nm decreased significantly in less than a few minutes at room temperature. We studied the effect of the length of alkyl chain in chalcone derivatives and found that the alignment properties are very much dependent on the chain length.