Reduced ionic contaminations in CdSe quantum dot dispersed ferroelectric liquid crystal and its applications

Abstract

Octadecylamine capped cadmium selenide quantum dots (CdSe QDs) were dispersed in the ferroelectric liquid crystal (FLC) FELIX 16/100. The QD dispersed FLC system was investigated on the planar anchored cell. Addition of specific concentration of the QDs in the pure FLC induces a new relaxation mode along with the Goldstone relaxation mode. QDs assisted quantum fluctuations are probably responsible for the existence of this new relaxation mode in the QDs dispersed FLC system. The ionic contaminations associated with the FLC materials were trapped on the surface of QDs due to the ion-trapping character of QDs. The trapping of ionic contaminations was confirmed by the a.c. conductivity measurement. The physical properties of the pure and dispersed FLC were carried out as a function of doping concentration of QDs, temperature and frequency.

Keywords:

• quantum dots
• relative permittivity
• ion-trapping
• conductivity

Acknowledgements

The authors are thankful to Department of Science and Technology, Government of India, for the financial assistance for the present work in the form of project.

Funding

The authors DPS and SKG are thankful to CSIR, India, for the grant of SRF fellowship Nos. 09/107(0363)2012-EMR-I and 09/107(0337)2010-EMR-I, respectively.