Regular Article - Solid State and Materials
The superconducting fluctuation optical conductivity of iron-based superconductors
Laboratory of Magnetism and Magnetic Materials, Science and Technology Advanced Institute, Van Lang University, Ho Chi Minh City, Vietnam
2 Faculty of Applied Technology, School of Technology, Van Lang University, Ho Chi Minh City, Vietnam
3 Faculty of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Ha Noi, Vietnam
Accepted: 23 August 2023
Published online: 29 August 2023
We investigate the superconducting fluctuation optical conductivity using the time-dependent Ginzburg–Landau Lawrence–Doniach model with thermal noise describing strong thermal fluctuation in iron-based superconductors. The superconducting fluctuation optical conductivity as temperature in the homogeneous phase is calculated. The experimental data of iron-based superconductors FeSeTe are fitted using the theoretical result based on the self-consistent Gaussian approximation. Our results show the real and imaginary part of the superconducting fluctuation optical conductivity in a wide region around T are well described by the theoretical formula. The superfluid density is also in good agreement with the experimental data in both the superconducting state below T and the normal state above T. It shows that the superfluid density and the imaginary portion of the optical conductivity are still non-zero and considerably large for temperature above Tc, indicating the residual superconductivity above Tc due to strong thermal fluctuations.
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