najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2025-16-5-593-596najo-1530Research ArticlePHYSICSФИЗИКАInclusions of metastable superconducting phase of gallium in SmGa2Включения метастабильной сверхпроводящей фазы галлия в SmGa2https://orcid.org/0000-0002-2184-7054ШитовА. Е.ShitovA. E.

Санкт-Петербург

Alexander E. Shitov

26 Politekhnicheskaya st., Saint Petersburg, 194021

aa.shitov@mail.ioffe.ruhttps://orcid.org/0000-0003-4007-5640ВолковМ. П.VolkovM. P.

Санкт-Петербург

Mikhail P. Volkov

26 Politekhnicheskaya st., Saint Petersburg, 194021

bm.volkov@mail.ioffe.ruФизико-технический институт им. А.Ф. Иоффе РАНIoffe Institute202505112025165593596Copyright © Shitov A.E., Volkov M.P., 20252025Шитов А.Е., Волков М.П.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/1530

The magnetization M of the SmGa2 compound has a paramagnetic character in a wide temperature range, and when the temperature decreases below 30 K, a significant increase in magnetization is observed, 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.

Намагниченность M соединения SmGa2 в широкой области температур имеет парамагнитный характер, а при понижении температуры ниже 30 K наблюдается существенный рост намагниченности, который указывает на образование магнитоупорядоченного состояния. При температурах ниже 5 К на зависимостях M(H) наблюдается резкая особенность, представляющая собой вклад от намагниченности сверхпроводящих суб-микронных включений галлия. Анализ зависимостей M(H), измеренных при разных температурах ниже 5 К, позволил предположить наличие двух сверхпроводящих фаз галлия. Критическая температура TC = 5.9 K и критическое поле HC (0) = 560 Oe соответствуют образованию метастабильной β-фазы галлия, а критическая температура TC = 8.4 K и критическое поле HC (0) = 1100 Oe могут быть связаны с образованием тонкого слоя аморфного галлия на поверхности включений β-фазы.

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