Time-Resolved Investigation of PhotocurrentRelaxation in Ionic Conductor Beta-AgI forDifferent Temperatures

Authors

DOI:

https://doi.org/10.53799/pzmcd761

Keywords:

Beta-AgI, bandgap, Decay dynamics, Photocurrent, Time-resolved measurement

Abstract

Time-resolved measurements of photoirradiation effects provide an intimate understanding of the processes involved in photoexcited systems. In this work, we measured time-resolved photocurrents of KI-treated -AgI polycrystals, which provide information about the primary process underlying the photoinduced change in the ionic conductivity of -AgI. Two excitation wavelengths, 450 nm and 532 nm, corresponding to excitation at the band-gap edge and in the sub-band-gap region, respectively, were used to photoirradiate the samples. The transient photocurrents measured by shining -AgI pellets with a nanosecond pulsed laser show fast and slow decay components in the nanosecond and microsecond time regions at both room temperature (298 K) and liquid nitrogen temperature (77 K). The remarkable photocurrent observed at room temperature was significantly suppressed at 77 K. The photocurrent relaxation also showed a clear temperature dependence: the photocurrent relaxation time (the averaged decay time) observed at room temperature was in the range of 2-3 s, while a faster photocurrent relaxation in the range of 0.3-0.4 s was observed at 77 K. Although the decrease in average relaxation time at 77 K does not represent a uniform decrease across all relaxation processes, the component 3 (3) process shows a significant increase at 77 K compared to 298 K.

Author Biography

  • Farzana Sabeth, American International University-Bangladesh, Hokkaido University

    Dr. Farzana Sabeth began her academic journey by earning a Bachelor of Science and a Master of Science in Physics from the University of Dhaka, laying the foundation for her subsequent specialization. In November 2002, she began her professional career as a Lecturer at the American International University-Bangladesh, where she cultivated her expertise. In 2008, she pursued advanced doctoral studies at Hokkaido University in Japan, culminating in a PhD in 2012. Following her doctoral success, she continued her scholarly pursuits through a postdoctoral fellowship at the same institution, further refining her experimental methodologies. Her current research focuses on advancing the understanding of physical phenomena, reflecting a sustained engagement with both theoretical inquiry and practical applications within the academic sphere. Her scholarly output is characterized by a multidisciplinary approach, emphasizing the synthesis and analysis of advanced materials to address contemporary scientific challenges. Furthermore, her recent work explores the optimization of nanostructured systems, contributing to a broader understanding of energy efficiency and material performance.

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Published

30-10-2026

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Vol. 25 No. 2 (2026): AJSE Volume 25 Issue 2

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How to Cite

[1]
“Time-Resolved Investigation of PhotocurrentRelaxation in Ionic Conductor Beta-AgI forDifferent Temperatures”, AJSE, vol. 25, no. 2, pp. 180–187, Oct. 2026, doi: 10.53799/pzmcd761.