Pico-ampere current sensitivity and CdSe quantum dots assembly assisted charge transport in ferroelectric liquid crystal. (18th July 2017)

• Record Type: Journal Article
• Authors: Singh, Dharmendra Pratap; Boussoualem, Yahia; Duponchel, Benoit; Hadj Sahraoui, Abdelhak; Kumar, Sandeep; Manohar, Rajiv; Daoudi, Abdelylah
• Is Part Of: Journal of physics. Volume 50:Number 32(2017)
• Publication Date: 2017-07-18
• Subjects: molecular assembly -- charges transport -- electro-optical effect -- quantum dots; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/aa7ae5
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: Octadecylamine capped CdSe quantum dots (QDs) dispersed 4-(1-methyl-heptyloxy)-benzoic acid 4′-octyloxy-biphenyl-4-yl ester ferroelectric liquid crystal (FLC) were deposited over gold coated quartz substrate using dip-coating. The topographical investigation discloses that the homogeneously dispersed QDs adopt face-on to edge-on assembly in FLC matrix owing to their concentration. Current–voltage ( I – V ) measurement was performed using conductive atomic force microscopy (CAFM) which yields ohmic to critical diode like I – V curves depending upon the concentration of QDs in FLC. The recorded pico-ampere (pA) current sensitivity in FLC-QDs composites is attributed to micro-second drift time of electron due to weak electronic coupling between the π -electrons on the FLC and s-electrons on the metal surface. The observed pico-ampere sensitivity is the least current sensitivity recorded so far. For FLC-QDs composites, almost 24% faster electro-optic response was observed in comparison to pure FLC. The pico-ampere current sensitivity can be utilized in touch screen displays whereas the change in polarization for low applied electric field ameliorates the increased electrical susceptibility counteracting the internal electric field and its use in electronic data storage and faster electro-optical devices.