Dissertation/ Thesis
Fermi liquid properties of Sr2RuO4 and nematicity in Ba(Fe(1-x)Co(x))2As2 superconductor : studies by Raman and elasto-Raman spectroscopies ; Propriétés de liquide de Fermi de Sr2RuO4 et nématicité dans le supraconducteur Ba(Fe(1-x)Co(x))2As2 : études par spectroscopies Raman et élasto-Raman
| العنوان: | Fermi liquid properties of Sr2RuO4 and nematicity in Ba(Fe(1-x)Co(x))2As2 superconductor : studies by Raman and elasto-Raman spectroscopies ; Propriétés de liquide de Fermi de Sr2RuO4 et nématicité dans le supraconducteur Ba(Fe(1-x)Co(x))2As2 : études par spectroscopies Raman et élasto-Raman |
|---|---|
| المؤلفون: | Philippe, Jean-Côme |
| المساهمون: | Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université Paris Cité, Yann Gallais |
| المصدر: | https://theses.hal.science/tel-03967012 ; Chimie-Physique [physics.chem-ph]. Université Paris Cité, 2021. Français. ⟨NNT : 2021UNIP7196⟩. |
| بيانات النشر: | HAL CCSD |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | Raman spectroscopy, Uniaxial stress, Superconductivity, Nematicity, Fermi liquid, Spectroscopie Raman, Contrainte uniaxiale, Supraconductivité, Nématicité, Liquide de Fermi, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph] |
| الوصف: | In quantum materials, interactions between quasiparticules spawn quantum collective orders, including superconductivity. In iron-based superconductors, the superconducting properties are significantly influenced by a close nematic order, leading in particular to a relatively high superconducting critical temperature. Uniaxial stress is a key parameter to tune nematic materials, and more generally superconductors whose fundamental state has a multi-component representation. Substantial changes in the critical temperature upon applying uniaxial stress have been experimentally demonstrated in Ba(Fe1¿xCox)2As2 and Sr2RuO4. These findings show the possibility to tune the superconducting properties through uniaxial stress, and conversely provide a better understanding of this order. These results follow the recent development of cells capable of applying well-controlled and strong uniaxial stress, used within various and complementary experimental set-ups. Raman spectroscopy is a unique probe of electronic states, which can resolve their different symetries. During my PhD, I have developped an elasto-Raman spectroscopy device, combining Raman spectroscopy and uniaxial stress. With this set-up, I studied Ba(Fe1¿xCox)2As2. I show that the intensity of the arsenic phonon mode can be interpretated as a nematic order parameter. Its evolution with both temperature and uniaxial stress agrees with a second-order Ising-type phase transition. By studying the electronic continuum, I access the evolution of the nematic susceptibility in presence of an external field, both in the metallic and superconducting states. I observe a strong decrease of the nematic fluctuations induced by the uniaxial stress, which could be the source of the significant decrease of the superconducting critical temperature. I also studied Sr2RuO4. My Raman spectroscopy study of this material without applied stress shows that its Raman response is typical of the one expected for a Fermi liquid. I observe a symmetry differentiation, which I read as the ... |
| نوع الوثيقة: | doctoral or postdoctoral thesis |
| اللغة: | French |
| Relation: | NNT: 2021UNIP7196; tel-03967012; https://theses.hal.science/tel-03967012; https://theses.hal.science/tel-03967012/document; https://theses.hal.science/tel-03967012/file/va_Philippe_Jean-come.pdf |
| الاتاحة: | https://theses.hal.science/tel-03967012 https://theses.hal.science/tel-03967012/document https://theses.hal.science/tel-03967012/file/va_Philippe_Jean-come.pdf |
| Rights: | info:eu-repo/semantics/OpenAccess |
| رقم الانضمام: | edsbas.938FF223 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |