Dorota I Iwona Walicka, Olivier Blacque, Tomasz Klimczuk, Fabian Von Rohr
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 crystallizes into the centrosymmetric P6/mmm space group (a = 4.2555(2) ˚A, c = 4.7288(2) ˚A) with statistical disorder in the [GaGe]2- 6 honeycomb layers. On the other hand, we confirm that SrAlGe crystallizes in a non-centrosymmetric space group, namely P6m2 (a = 4.2942(1) ˚A, c = 4.7200(2) ˚A) with fully ordered [AlGe]2- 6 honeycomb layers. By using magnetization and specific heat measurements, we show that the superconducting properties of SrGaGe and SrAlGe differ significantly from each other. SrGaGe is a superconductor with a critical temperature of Tc = 2.6 K falling into the weak coupling limit, while SrAlGe has a Tc = 6.7 K and can be classified in the strong coupling limit. By realizing the SrGa1-x AlxGe solid solution, we were able to investigate the transition between 
 the different crystal structures as well as the evolution of the electronic properties. We show that the transition from the weak to the strong coupling superconductivity in this system is likely associated with the disorder-to-order transition of the honeycomb layer, along with the loss of the inversion center in the crystal structure.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Physics: Condensed Matter","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1088/1361-648X/ad8c0b","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, CONDENSED MATTER","Score":null,"Total":0}
引用次数: 0
Abstract
We report on the structure and the superconducting properties of 9-electron 111 compounds with honeycomb layers, namely SrGaGe, SrAlGe, and the SrGa1-x AlxGe solid solution. By means of single-crystal X-ray diffraction we show that, on one hand, SrGaGe
crystallizes into the centrosymmetric P6/mmm space group (a = 4.2555(2) ˚A, c = 4.7288(2) ˚A) with statistical disorder in the [GaGe]2- 6 honeycomb layers. On the other hand, we confirm that SrAlGe crystallizes in a non-centrosymmetric space group, namely P6m2 (a = 4.2942(1) ˚A, c = 4.7200(2) ˚A) with fully ordered [AlGe]2- 6 honeycomb layers. By using magnetization and specific heat measurements, we show that the superconducting properties of SrGaGe and SrAlGe differ significantly from each other. SrGaGe is a superconductor with a critical temperature of Tc = 2.6 K falling into the weak coupling limit, while SrAlGe has a Tc = 6.7 K and can be classified in the strong coupling limit. By realizing the SrGa1-x AlxGe solid solution, we were able to investigate the transition between
the different crystal structures as well as the evolution of the electronic properties. We show that the transition from the weak to the strong coupling superconductivity in this system is likely associated with the disorder-to-order transition of the honeycomb layer, along with the loss of the inversion center in the crystal structure.
期刊介绍:
Journal of Physics: Condensed Matter covers the whole of condensed matter physics including soft condensed matter and nanostructures. Papers may report experimental, theoretical and simulation studies. Note that papers must contain fundamental condensed matter science: papers reporting methods of materials preparation or properties of materials without novel condensed matter content will not be accepted.