najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМОnajo-335Research ArticlePHYSICSФИЗИКАInclusions of metastable superconducting phase of gallium in SmGa2ShitovAlexandr Evgenievicha.shitov@mail.ioffe.ruhttps://orcid.org/0000-0003-4007-5640VolkovMikhail Pavlovichm.volkov@mail.ioffe.ruIoffe InstituteRussian FederationФизико-технический институт им. А.Ф.Иоффе, Санкт-ПетербургIoffe Institute202505022026165335Copyright © Shitov A.E., Volkov M.P., 20252025Shitov A.E., Volkov M.P.Shitov A.E., Volkov M.P.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/335

The magnetization M of the SmGa2 compound has a paramagnetic character in a wide temperature range, and a significant increase in magnetization is observed below 30 K, which indicates the formation of a magnetically ordered state. At temperatures below 5 K, a sharp feature is observed on the M(H) dependences, which is the contribution from the magnetization of superconducting submicron gallium inclusions. Analysis of the M(H) dependences measured at different temperatures below 5 K allowed us to assume the presence of two superconducting gallium phases. The critical temperature TC = 5.9 K and the critical field HC(0) = 560 Oe correspond to the formation of a metastable β-phase of gallium, and the critical temperature TC = 8.4 K and the critical field HC(0) = 1100 Oe can be associated with the formation of a thin layer of amorphous gallium on the surface of the β-phase inclusions. 

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The authors declare that there are no conflicts of interest present.