Sangkook Choi

Korea Institute for Advanced Study (KIAS), Korea

15 February 2023 Wed 3.30 pm

                                      IBS Center for Theoretical Physics of Complex Systems (PCS), Administrative Office (B349), Theory Wing, 3rd floor

                                      Expo-ro 55, Yuseong-gu, Daejeon, South Korea, 34126 Tel: +82-42-878-8633                     

Quantum information science is a surging frontier of physical science. By creating quantum states and utilizing them as quantum bits (qubits), it promises vastly improved performance over what we have achieved during the 20th century. Quantum materials are a class of materials of which properties can be explained by only quantum physics. When their quantum nature is due to electron-electron interaction, quantum materials give rise to a rich tableau of novel physics. These so-called correlated quantum materials can be utilized as “semiconductors” for quantum information science. However, understanding correlated quantum materials properties is one of the grand challenges in the field of quantum materials. Correlated quantum materials preclude simple explanations and computationally simple methods based on Landau’s Fermi liquid theory, such as density functional theory. In this talk, I'll introduce ab initio DMFT approaches, especially LQSGW+DMFT[1,2] and full GW+EDMFT. I will also show several interesting physics found in correlated quantum material including infinite-layer nickelate [3,4], Fe-based superconductors and Fe-based narrow-gap semiconductors [5]. 


[1] S. Choi, P. Semon, B. Kang, A. Kutepov, and G. Kotliar, Comp. Phys. Comm. 244, 277 (2019)

[2] S. Choi, A. Kutepov, K. Haule, M. van Schilfgaarde, and G. Kotliar, npj Quantum Materials 1, 16001 (2016)

[3] S. Ryee, P. Semon, M. J. Han+, and S. Choi+ , Phys. Rev. Lett. 126, 206401 (2021); 

[4] B. Kang, C. Melnick, P. Semon, S. Ryee, M. J. Han, G. Kotliar, and S. Choi, arXiv:2007.14610

[5] C. C. Homes, Q. Du, C. Petrovic, W. H. Brito, S. Choi, and G. Kotliar, Scientific Reports 8, (2018).

  1. ab initio dmft methodologies for correlated quantum materials