Nicola Lanatà, PhD
National High Magnetic Field Laboratory (MagLab), Florida State University, United States

Abstract:
The choice that a solid system "makes" when adopting a crystal structure (stable or metastable) is ultimately governed by the interactions between electrons forming chemical bonds. By analyzing 6 prototypical binary transition-metal compounds we demonstrate here that the orbitally-selective strong d-electron correlations influence dramatically the behavior of the energy as a function of the spatial arrangements of the atoms. Remarkably, we find that the key physical mechanism underlying this complex behavior can be traced back to simple electrostatics, i.e., to the fact that the strong d-electron correlations influence substantially the charge transfer mechanism, which, in turn, controls the electrostatic interactions. This result advances our understanding of the influences of strong correlations on the crystal structure, opens a new avenue for extending structure prediction methodologies to strongly correlated materials, and paves the way for predicting and studying metastability and polymorphism in these systems.

Biography:
Nicola Lanatà obtained his PhD in “Theory and Numerical Simulation in Condensed Matter Systems” at the International School for Advanced Studies (SISSA-ISAS) (Italy) in October 2009, under the supervision of Prof. Michele Fabrizio. He subsequently worked for two years as a postdoc at the Gothenburg University (Sweden), and for another three years at Rutgers University (USA), under the supervision of Prof. Gabriel Kotliar. In September 2015, he joined the National High Magnetic Field Laboratory (MagLab) as a Dirac Postdoctoral Fellow. His research activity has been mainly concerned with the physics of Strongly Correlated Materials, Materials Science and the development of new theoretical and computational methods, including an open-source code awarded with the “Ames Laboratory Patent Award” in March 2014.

References:
[1] Tsung-Han Lee, Yong-Xin Yao, Vladan Stevanovic and Vladimir Dobrosavljevi?, Nicola Lanatà, “Critical role of Electronic Correlations in determining Crystal Structure of Transition Metal Compounds” arXiv: 1710.08586 (2017).
[2] Nicola Lanatà, Yong-Xin Yao, Xiaoyu Deng, Vladimir Dobrosavljevi? and Gabriel Kotliar, “Slave Boson Theory of Orbital Differentiation with Crystal Field Effects: Application to UO2”, Phys. Rev. Lett. 118, 126401 (2017).
[3] Nicola Lanatà, Yong-Xin Yao, Cai-Zhuang Wang, Kai-Ming Ho and Gabriel Kotliar, “Phase Diagram and Electronic Structure of Praseodymium and Plutonium”, Phys. Rev. X 5, 011008 (2015).