{"title":"重费米子UTe2 超导体的热力学和磁学特性","authors":"Habtamu Anagaw, Gebregziabher Kahsay, Tamiru Negussie","doi":"10.1134/S1063783424600729","DOIUrl":null,"url":null,"abstract":"<p>In the current study, the density of state, condensation energy, specific heat, and magnetization in a spin triplet superconductor UTe<sub>2</sub> have been theoretically investigated. By utilizing the retarded double-time temperature-dependent Green’s function formalism and constructing a model Hamiltonian for the system, we derived expressions for the aforementioned parameters. MATLAB scripts were used to plot the phase diagrams. From the phase diagrams, we observed that the density of state of superconducting electron increases with excitation energy, reaching a maximum at the superconducting gap. Beyond this point, it decreases until it equals the normal state density. Condensation energy decreases with temperature, reaching a minimum at the superconducting transition temperature (<i>T</i><sub>C</sub>). However, it increases with <i>T</i><sub>C</sub> and eventually becomes zero, indicating that the superconducting and normal state energies are equal. Furhermore, specific heat increases with temperature, exhibiting a maximum at <i>T</i><sub>C</sub> followed by a jump, characteristic of a second-order phase transition from the superconducting to the normal state. Both itinerant and localized electron magnetization decrease with temperature, vanishing at <i>T</i><sub>C</sub> = 1.6 K and magnetic phase transition temperature <i>T</i> = 2 K, respectively, signifying a ferromagnetic to paramagnetic transition. Our findings align well with previous research.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"66 9","pages":"349 - 363"},"PeriodicalIF":0.9000,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Thermodynamic and Magnetic Properties of Heavy Fermion UTe2 Superconductor\",\"authors\":\"Habtamu Anagaw, Gebregziabher Kahsay, Tamiru Negussie\",\"doi\":\"10.1134/S1063783424600729\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>In the current study, the density of state, condensation energy, specific heat, and magnetization in a spin triplet superconductor UTe<sub>2</sub> have been theoretically investigated. By utilizing the retarded double-time temperature-dependent Green’s function formalism and constructing a model Hamiltonian for the system, we derived expressions for the aforementioned parameters. MATLAB scripts were used to plot the phase diagrams. From the phase diagrams, we observed that the density of state of superconducting electron increases with excitation energy, reaching a maximum at the superconducting gap. Beyond this point, it decreases until it equals the normal state density. Condensation energy decreases with temperature, reaching a minimum at the superconducting transition temperature (<i>T</i><sub>C</sub>). However, it increases with <i>T</i><sub>C</sub> and eventually becomes zero, indicating that the superconducting and normal state energies are equal. Furhermore, specific heat increases with temperature, exhibiting a maximum at <i>T</i><sub>C</sub> followed by a jump, characteristic of a second-order phase transition from the superconducting to the normal state. Both itinerant and localized electron magnetization decrease with temperature, vanishing at <i>T</i><sub>C</sub> = 1.6 K and magnetic phase transition temperature <i>T</i> = 2 K, respectively, signifying a ferromagnetic to paramagnetic transition. Our findings align well with previous research.</p>\",\"PeriodicalId\":731,\"journal\":{\"name\":\"Physics of the Solid State\",\"volume\":\"66 9\",\"pages\":\"349 - 363\"},\"PeriodicalIF\":0.9000,\"publicationDate\":\"2024-10-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Physics of the Solid State\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://link.springer.com/article/10.1134/S1063783424600729\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"PHYSICS, CONDENSED MATTER\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics of the Solid State","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1134/S1063783424600729","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PHYSICS, CONDENSED MATTER","Score":null,"Total":0}
引用次数: 0
摘要
本研究对自旋三重超导体UTe2 的状态密度、凝结能、比热和磁化进行了理论研究。通过利用迟滞双时温度相关格林函数形式主义和构建系统的模型哈密顿,我们推导出了上述参数的表达式。我们使用 MATLAB 脚本绘制了相图。从相图中我们观察到,超导电子的状态密度随激发能量的增加而增加,在超导间隙处达到最大值。超过这一点后,电子的状态密度会逐渐减小,直至与正常状态密度相等。凝结能随温度的升高而降低,在超导转变温度(TC)处达到最小值。然而,凝结能随温度升高而增加,最终变为零,表明超导态能量和正常态能量相等。此外,比热随温度升高而增加,在超导转变温度达到最大值后出现跃迁,这是从超导态到正常态的二阶相变的特征。巡回磁化和局部电子磁化均随温度降低而减小,分别在 TC = 1.6 K 和磁相变温度 T = 2 K 时消失,这意味着铁磁性向顺磁性的转变。我们的研究结果与之前的研究结果非常吻合。
Thermodynamic and Magnetic Properties of Heavy Fermion UTe2 Superconductor
In the current study, the density of state, condensation energy, specific heat, and magnetization in a spin triplet superconductor UTe2 have been theoretically investigated. By utilizing the retarded double-time temperature-dependent Green’s function formalism and constructing a model Hamiltonian for the system, we derived expressions for the aforementioned parameters. MATLAB scripts were used to plot the phase diagrams. From the phase diagrams, we observed that the density of state of superconducting electron increases with excitation energy, reaching a maximum at the superconducting gap. Beyond this point, it decreases until it equals the normal state density. Condensation energy decreases with temperature, reaching a minimum at the superconducting transition temperature (TC). However, it increases with TC and eventually becomes zero, indicating that the superconducting and normal state energies are equal. Furhermore, specific heat increases with temperature, exhibiting a maximum at TC followed by a jump, characteristic of a second-order phase transition from the superconducting to the normal state. Both itinerant and localized electron magnetization decrease with temperature, vanishing at TC = 1.6 K and magnetic phase transition temperature T = 2 K, respectively, signifying a ferromagnetic to paramagnetic transition. Our findings align well with previous research.
期刊介绍:
Presents the latest results from Russia’s leading researchers in condensed matter physics at the Russian Academy of Sciences and other prestigious institutions. Covers all areas of solid state physics including solid state optics, solid state acoustics, electronic and vibrational spectra, phase transitions, ferroelectricity, magnetism, and superconductivity. Also presents review papers on the most important problems in solid state physics.