Resolving Emergent Structure States in Quantum Materials by Total X-Ray Scattering

Materials with properties rooted in the quantum world exhibit coupled electronic, magnetic and lattice degrees of freedom leading to fascinating properties. However, the lattice degrees of freedom often appear as lattice distortions which are not necessarily amenable to crystallographic description, hampering the understanding of the underlaying physics. In the talk, we will show that the problem may be solved by total x-ray scattering and show examples from our recent studies on dual heavy fermion liquid UPt₂Si₂, which exhibits antiferromagnetism consistent with localized 5f-electron states and transport properties characteristic to Kondo lattice systems (1), layered transition metal dichalcogenide 1T-TaS₂, which is a putative Mott insulator (2), and NbTe₄topological superconductor, where double Dirac points emerge thanks to the emergence of charge density wave order (3).<br/><br/>(1) V. Petkov, R. Baumbach, AM Milinda Abeykoon and J. A. Maydosh “3D charge density wave in the dual fermion system UPt2Si2” <i>Phys. Rev. B</i> <b>107</b>, 245101 (2023).<br/>(2) V. Petkov, J. Peralta, B. Aoun and Y. Ren “Atomic structure and Mott nature of the insulating charge density wave phase in 1T-TaS₂” <i>J. Phys.: Condens. Mater</i> <b>34,</b> 345401 (2022).<br/>(3) V. Petkov, R. Amin, M. Jakhar, AM Milinda Abeykoon and X. Ke“Charge density wave order, local lattice distortions and topological electronic states in NbTe₄” <i>Phys. Rev. Lett</i>. (under review).