Abstract
Frequency and temperature dependences of dielectric constant, dielectric loss and ac electrical conductivity were studied for bulk Se70Bi30 and Se70Bi15Te15 chalcogenide glasses, in the frequency range (1–100kHz) and temperature range below glass transition temperatures. Both dielectric constant and dielectric loss are found to decrease with increasing frequency and decreasing temperature. An analysis of dielectric loss data obeyed the Guintini's theory of dielectric dispersion based on hopping model. The Cole–Cole diagram has been used to determine some parameters such as the distribution parameter, molecular relaxation time and activation energy for relaxation. The ac conductivity was found proportional to ωs. The variation of both the frequency exponent and ac conductivity with temperature suggested that, the ac conductivity is explained according to correlated barrier hopping (CBH) model, with activation energy decreasing with increasing frequency for Se70Bi30 and Se70Bi15Te15 samples. The addition of Te atoms leads to an increase in the density of localized states in the tails and consequently increases ac conductivity.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
