Physics and Technology of Cuprate HTSC

Despite more than 30 years of research history, the question of the physical nature of the normal state and the mechanism of superconductivity in various families of high-temperature superconductors remains a subject of discussion. In the context of searching for an answer to these global questions, it is necessary to study and understand many anomalous properties of HTSC, which manifest themselves both in the superconducting and normal states. These include the linear temperature dependence of electrical resistance, the transfer of spectral weight to the high-frequency region, the reversibility of magnetization curves, the existence of “magic” values of dopant concentration corresponding to sharp changes in superconducting properties, etc.

Experimental studies in this area require high-quality and well-certified samples. Therefore, our group is working on the development of technology and fabrication of thin-film structures and heterostructures based on HTSC (cuprates, pnictides, selenides and nickelates) by pulsed laser deposition (PLD) and magnetron sputtering. The main focus is on obtaining epitaxial HTSC films suitable for both physical searches and study of their functional characteristics, which determine the possibility of their application in various fields of technique. To characterize the structures, studies of their magnetotransport, structural, optical and other properties are carried out.

Main results

In the context of addressing the problem of clarifying the physical nature of the normal state and the mechanism of superconductivity, we propose a unified view on the transformation of the electronic structure of cuprates and ferropnictides upon heterovalent and isovalent doping, based on the assumption of self-localization of doped carriers. In this representation, in undoped cuprates and ferropnictides, which initially have different electronic structures (Mott insulator and semimetal), local doping forms percolation
clusters with the same electronic structure of a self-doped excitonic insulator where a specific mechanism of superconducting pairing is implemented, which is genetically inherent in such a system. The proposed model includes a mechanism for generating additional free carriers under heterovalent and isovalent doping and makes it possible to predict their sign, which, in the general case, does not coincide with the sign of doped carriers.

M.V. Golovin

MIPT student

M.A. Lomsargis

HSE student

Publications

1.Mitsen K., Ivanenko O. Physical Nature of the Pseudogap Phase and Anomalous Transfer of Spectral Weight in Underdoped Cuprates //Journal of Superconductivity and Novel Magnetism. – 2024. – С. 1-12; DOI 10.1007/s10948-024-06782-x. https://arxiv.org/abs/2401.12647
1.Mitsen K., Ivanenko O. Local transformation of the electronic structure and generation of free carriers in cuprates and ferropnictides under heterovalent and isovalent doping //Results in Physics. – 2022. – Т. 38. – С. 105577; DOI 10.1016/j.rinp.2022.105577. https://www.sciencedirect.com/science/article/pii/S221137972200300X/pdfft?md5=b05776da226e3f5457710335e256f43c&pid=1-s2.0-S221137972200300X-main.pdf
1.Mitsen K. V., Ivanenko O. M. Cluster structure of superconducting phase and the nature of peaks in the doping dependences of the London penetration depth in iron pnictides //Results in Physics. – 2022. – Т. 32. – С. 105156; DOI 10.1016/j.rinp.2021.105156. https://www.sciencedirect.com/science/article/pii/S2211379721011141/pdfft?md5=430e8e69ef49b545641103cda3136218&pid=1-s2.0-S2211379721011141-main.pdf
1.Mitsen K. V., Ivanenko O. M. On the Nature of Scaling Relations in Cuprate HTSCs //Bulletin of the Lebedev Physics Institute. – 2021. – Т. 48. – С. 346-348; DOI 10.3103/S1068335621110075
5.Mitsen K., Ivanenko O. The mechanism of doping and the features of phase diagrams of HTSC cuprates and ferropnictides //Journal of Superconductivity and Novel Magnetism. – 2020. – Т. 33. – С. 2637-2648; DOI 10.1007/s10948-020-05512-3
5.Mitsen K., Ivanenko O. Towards the issue of the origin of Fermi surface, pseudogaps and Fermi arcs in cuprate HTSCs //Journal of Alloys and Compounds. – 2019. – Т. 791. – С. 30-38; DOI 10.1016/j.jallcom.2019.03.273. https://arxiv.org/pdf/1801.06487
7.Y. A. Aleshchenko, A. V. Muratov, E. S. Zhukova, L. S. Kadyrov, B. P. Gorshunov, G. A. Ummarino, I. A. Shipulin “THz optical response of Ba(Fe1-xNix)2As2 films analyzed within the three-band Eliashberg s±-wave model” // Journal of Physics and Chemistry of Solids 2025, 196 112364; https://doi.org/10.1016/j.jpcs.2024.112364
7.Y. A. Aleshchenko, A. V. Muratov, E. S. Zhukova, L. S. Kadyrov, B. P. Gorshunov, G. A. Ummarino, I. A. Shipulin “Optical and transport properties of Ba(Fe1-xNix)2As2 films” // Solid State Sciences 2025, 160 107787; https://doi.org/10.1016/j.solidstatesciences.2024.107787
7.I. A. Shipulin, K. Nielsch and R. Hühne “Comprehensive study of epitaxial (Nd,Eu,Gd)Ba2Cu3O7−δ films grown on textured templates” // Physica Scripta 2024, 99 115965; https://iopscience.iop.org/article/10.1088/1402-4896/ad8380
7.I. Shipulin, N. Stegani, I. Maccari, K. Kihou, C.-H. Lee, R. Hühne, F. Caglieris, E. Babaev, and V. Grinenko ” Calorimetric evidence for two phase transitions in Ba1-xKxFe2As2 with fermion pairing and quadrupling state” // Nature Communication 2023, 14 6734; https://doi.org/10.1038/s41467-023-42459-0
7.R. Khasanov, A. Ramires, V. Grinenko, I. Shipulin, N. Kikugawa, D. A. Sokolov, Y. Maeno, H. Luetkens, and Z. Guguchia ” In-plane magnetic penetration depth in Sr2RuO4: muon-spin rotation/relaxation study” Physical Review Letters 2023, 131, 236001; https://doi.org/10.1103/PhysRevLett.131.236001
7.V. Grinenko, R. Sarkar, S. Ghosh, D. Das, Z. Guguchia, H. Luetkens, M. Sigrist, I. Shipulin, A. Ramires, N. Kikugawa, Y. Maeno, K. Ishida, C. W. Hicks, and H.-H. Klauss “µSR measurements on Sr2RuO4 under ⟨110⟩ uniaxial stress” // Phys. Rev. B 2023, 107 024508; https://doi.org/10.1103/PhysRevB.107.024508