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arXiv · 2108.13928

Novel magnetic stoichiometric superconductor EuRbFe4As4

T. K. Kim·K. S. Pervakov·V. A. Vlasenko·A. V. Sadakov·A. S. Usoltsev·D. V. Evtushinsky·S. W. Jung·G. Poelchen·K. Kummer·D. Roditchev·V. S. Stolyarov·I. A. Golovchanskiy·D. V. Vyalikh·V. Borisov·R. Valenti·A. Ernst·S. V. Eremeev·E. V. Chulkov·V. M. Pudalov
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Abstract

In the novel stoichiometric iron-based material RbEuFe4As4 superconductivity coexists with a peculiar long-range magnetic order of Eu 4f states; their coexistance is puzzling and represents a challenge for both experiment and theory. Using angle-resolved photoemission spectroscopy, resonant photoemission spectroscopy, Andreev reflection spectroscopy and scanning tunneling spectroscopy we have addressed this puzzle and unambigously shown that Fe- and Eu-derived states are largely decoupled and that superconducting and a long range magnetic orders exist almost independently from each other.

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T. K. Kim, K. S. Pervakov, V. A. Vlasenko, A. V. Sadakov, A. S. Usoltsev, D. V. Evtushinsky, S. W. Jung, G. Poelchen, K. Kummer, D. Roditchev, V. S. Stolyarov, I. A. Golovchanskiy, D. V. Vyalikh, V. Borisov, R. Valenti, A. Ernst, S. V. Eremeev, E. V. Chulkov, V. M. Pudalov. 2021-08-31. Novel magnetic stoichiometric superconductor EuRbFe4As4. https://doi.org/10.3367/ufne.2021.05.039018

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