Multiple Andreev Reflection Effect Spectroscopy of Underdoped NaFe1 – xCoxAs Single Crystals
- Authors: Kuz'michev S.A1,2, Morozov I.V3, Shilov A.I1, Rakhmanov E.O1,3, Kuz'micheva T.E1
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Affiliations:
- Lebedev Physical Institute, Russian Academy of Sciences, 119991, Moscow, Russia
- Faculty of Physics, Moscow State University, 119991, Moscow, Russia
- Faculty of Chemistry, Moscow State University, 119991, Moscow, Russia
- Issue: Vol 117, No 7-8 (4) (2023)
- Pages: 614-619
- Section: Articles
- URL: https://journals.rcsi.science/0370-274X/article/view/145197
- DOI: https://doi.org/10.31857/S1234567823080098
- EDN: https://elibrary.ru/WGAJFI
- ID: 145197
Cite item
Abstract
We study the structure of the superconducting order parameter in underdoped NaFe1 – xCoxAs pnictides with Tc ≈ 19–21 K related to the 111 family. Using incoherent multiple Andreev reflection effect spectroscopy of planar break junctions, we directly determine the magnitudes of the two microscopic superconducting order parameters: the small superconducting gap ΔS(0), and possible edges of the large gap ΔL(0) having an anisotropy in the
plane at T ≪ Tc, the corresponding characteristic ratios, as well as their temperature dependences. Additionally, we detect features of the tunneling spectra in NaFe1 – xCoxAs at
, those irrelative to superconducting state, and discuss their origin.
About the authors
S. A Kuz'michev
Lebedev Physical Institute, Russian Academy of Sciences, 119991, Moscow, Russia; Faculty of Physics, Moscow State University, 119991, Moscow, Russia
Email: kuzmichevate@lebedev.ru
I. V Morozov
Faculty of Chemistry, Moscow State University, 119991, Moscow, Russia
Email: kuzmichevate@lebedev.ru
A. I Shilov
Lebedev Physical Institute, Russian Academy of Sciences, 119991, Moscow, Russia
Email: kuzmichevate@lebedev.ru
E. O Rakhmanov
Lebedev Physical Institute, Russian Academy of Sciences, 119991, Moscow, Russia; Faculty of Chemistry, Moscow State University, 119991, Moscow, Russia
Email: kuzmichevate@lebedev.ru
T. E Kuz'micheva
Lebedev Physical Institute, Russian Academy of Sciences, 119991, Moscow, Russia
Author for correspondence.
Email: kuzmichevate@lebedev.ru
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