najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2025-16-1-67-73najo-92Research ArticleCHEMISTRY AND MATERIALS SCIENCEХИМИЯ И НАУКА О МАТЕРИАЛАХApplication of the numerical model of temperature-dependent thermal conductivity in Ca1-xYxF2+x heterovalent solid solution nanocompositesПрименение численной модели температурозависимой теплопроводности в гетеровалентных нанокомпозитах твердого раствора Ca1-xYxF2+xhttps://orcid.org/0000-0001-7555-1390ПоповП. А.PopovP. A.

Pavel A. Popov

14 Bezhitskaya str., Bryansk, 241036

tfbgubry@mail.ruhttps://orcid.org/0009-0001-4090-2506ЩелоковА. В.ShchelokovA. V.

Alexandr V. Shchelokov

14 Bezhitskaya str., Bryansk, 241036

alexandershchelokov@mail.ruhttps://orcid.org/0000-0002-6028-8937КонюшкинВ. А.KonyushkinV. A.

Vasilii A. Konyushkin

38 Vavilova str., Moscow, 119991

vasil@lst.gpi.ruhttps://orcid.org/0000-0002-4060-8091НакладовА. Н.NakladovA. N.

Andrey N. Nakladov

38 Vavilova str., Moscow, 119991

andy-nak@yandex.ruhttps://orcid.org/0000-0002-2918-3926ФедоровП. П.FedorovP. P.

Pavel P. Fedorov

38 Vavilova str., Moscow, 119991

ppfedorov@yandex.ruPetrovsky Bryansk State UniversityRussian FederationProkhorov General Physics Institute of the Russian Academy of SciencesRussian Federation2025010620251616773Copyright © Popov P.A., Shchelokov A.V., Konyushkin V.A., Nakladov A.N., Fedorov P.P., 20252025Попов П.А., Щелоков А.В., Конюшкин В.А., Накладов А.Н., Федоров П.П.Popov P.A., Shchelokov A.V., Konyushkin V.A., Nakladov A.N., Fedorov P.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/92

A series of Ca1-xYxF2+x solid solution x = 0:0005, 0:003, 0:007, 0:013, 0:02, 0:03, 0:04 single crystals were grown using the Bridgman method. The thermal conductivity of single crystals was measured using the absolute method of longitudinal heat flow in the range of 50 – 300 K. With an increase in the concentration of yttrium fluoride in the solid solution, a transition is observed from the temperature dependence characteristic of single crystals to a monotonically increasing one with increasing temperature, which is characteristic of disordered media. This behavior is associated with the scattering of phonons on nanosized clusters of defects present in the solid solution. Within the framework of a two-component model, including a superposition of thermal resistance coefficients from ordered and disordered media, a system of equations was obtained that provides a quantitative description of the experiment.

Методом Бриждмена выращена серия монокристаллов твердого раствора Ca1-xYxF2+x (х = 0.0005, 0.003, 0.007, 0.013, 0.02, 0.03, 0.04). Абсолютным методом продольного теплового потока измерена теплопроводность монокристаллов в интервале 50-300 К. При увеличении концентрации фторида иттрия в твердом растворе наблюдается переход от температурной зависимости, характерной для монокристаллов, к монотонно возрастающей с повышением температуры, что характерно для разупорядоченных сред. Такое поведение связывается с рассеянием фононов на наноразмерных кластерах дефектов, присутствующих в твердом растворе. В рамках двухкомпонентной модели, включающей суперпозицию коэффициентов теплового сопротивления от упорядоченной и разупорядоченной сред, получена система уравнений, дающая количественное описание эксперимента.

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