TY - JOUR T1 - Dielectric and Performance Analysis of CdTe Quantum Dots Doped Nematic Liquid Crystal TT - CdTe Kuantum Nokta Katkılı Nematik Sıvı Kristalin Dielektrik ve Performans Analizi AU - Köysal, Oğuz AU - Kocakülah, Gülsüm AU - Yıldırım, Mert AU - Önsal, Gülnur AU - Tüzün Özmen, Özge PY - 2018 DA - January DO - 10.29130/dubited.360125 JF - Duzce University Journal of Science and Technology JO - DÜBİTED PB - Duzce University WT - DergiPark SN - 2148-2446 SP - 254 EP - 262 VL - 6 IS - 1 LA - en AB - In this work, cadmium telluride core type quantum dots (CdTe QDs) weredispersed in 4-pentyl-4′-cyanobiphenyl (5CB) nematic liquid crystal (LC) with aconcentration of 0.05 % wt/wt; and their electrical and dielectric propertieswere investigated by using admittance measurements in the frequency range of100 Hz - 10 MHz. In order to determine the effects of CdTe QDs in 5CB nematicLC, dielectric anisotropy (∆ε), crossover frequency (fcrossover), critical frequency (fcritical), real and imaginary parts of permittivity (ε'and ε") of neat LC and CdTe QDs dispersed LC composites were obtainedusing the experimental data. Moreover, threshold voltage (Vth),splay elastic constant (K11) were also calculated. It was found thatVth and K11 of QDs dispersed LC are significantlydecreased due to the existence of CdTe QDs. KW - Nematic liquid crystal KW - quantum dot KW - electrical and dielectric properties N2 - Bu çalışmada çekirdek tipi kadmiyum tellür kuantum noktaları (CdTe QDs) ağırlıkça% 0,05 oranında 5CB (4-pentil-4'-siyanobifenil) nematik sıvı kristale (LC) katkılanmışve elektrik ve dielektrik özellikleri 100 Hz-10 MHz frekans aralığında empedansölçümleri kullanılarak araştırılmıştır. CdTe kuantum noktaların 5CB nematiksıvı kristal yapıda gösterdiği etkiyi belirlemek için dielektrik anizotropi(Δε), çapraz frekans (fcrossover), kritik frekans (fkritik),dielektrik sabiti (ε 've ε ") değerleri deneysel veriler kullanılarak eldeedilmiştir. Ayrıca, eşik voltajı (Vth) ve splay elastik sabiti (K11)hesaplanmıştır. CdTe katkılanmasıyla eşik voltajı (Vth) ve eğilme elastiksabiti (K11) önemli ölçüde azaldığı görülmüştür. CR - [1] U. B. Singh, R. Dhar, A. S. Pandey, S. Kumar, R. Dabrowski, and M. B. Pandey, “Electro-optical and dielectric properties of CdSe quantum dots and 6CHBT liquid crystals composites, ” AIP Advances, vol. 4, no. 11, pp. 117112-1 - 117112-9, 2014. CR - [2] P. Malik, A. Chaudhary, R. Mehra, and K. K. Raina, “Electrooptic and dielectric studies in cadmium sulphide nanorods/ferroelectric liquid crystal mixtures,” Advances in Condensed Matter Physics, vol. 2012, pp. 1-8, 2012. CR - [3] E. A. Konshina, E. O. Gavrish, A. O. Orlova, and M. V. 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