title: Electrical response of liquid crystal cells doped with multi-walled carbon nanotubes.
abstract: The inclusion of nanoparticles modifies a number of fundamental properties of many materials. Doping of nanoparticles in self-organized materials such as liquid crystals may be of interest for the reciprocal interaction between the matrix and the nanoparticles. Elongated nanoparticles and nanotubes can be aligned and reoriented by the liquid crystal, inducing noticeable changes in their optical and electrical properties. In this work, cells of liquid crystal doped with high aspect ratio multi-walled carbon nanotubes have been prepared, and their characteristic impedance has been studied at different frequencies and excitation voltages. The results demonstrate alterations in the anisotropic conductivity of the samples with the applied electric field, which can be followed by monitoring the impedance evolution with the excitation voltage. Results are consistent with a possible electric contact between the coated substrates of the LC cell caused by the reorientation of the nanotubes. The reversibility of the doped system upon removal of the electric field is quite low.
authors.affiliation: CEMDATIC, E.T.S.I. Telecomunicación, Universidad Politécnica de Madrid, Avda. Complutense 30, Madrid, E28040, Spain.
authors.forename: Amanda
authors.initials: A
authors.lastname: García-García
authors.affiliation: GDAF-UC3M, Departamento de Tecnología Electrónica, Universidad Carlos III de Madrid, Butarque 15, Leganés, E28911, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Vergaz
authors.affiliation: GDAF-UC3M, Departamento de Tecnología Electrónica, Universidad Carlos III de Madrid, Butarque 15, Leganés, E28911, Spain.
authors.forename: José Francisco
authors.initials: JF
authors.lastname: Algorri
authors.affiliation: CEMDATIC, E.T.S.I. Telecomunicación, Universidad Politécnica de Madrid, Avda. Complutense 30, Madrid, E28040, Spain.
authors.forename: Xabier
authors.initials: X
authors.lastname: Quintana
authors.affiliation: CEMDATIC, E.T.S.I. Telecomunicación, Universidad Politécnica de Madrid, Avda. Complutense 30, Madrid, E28040, Spain.
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Otón
keywords: Cole–Cole diagrams; PEDOT:PSS; carbon nanotubes; impedance; liquid crystal
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