CONVENER

Bongjae Kim (Kyungpook National University, Korea)

MEMBERS

Heungsik Kim (Kangwon National University, Korea)

Chang Jong Kang (Chungnam National University, Korea)

Ara Go (Chonnam National University, Korea)

Sooran Kim (Kyungpook National University, Korea)

Hee Chul Park (Pukyong National University, Korea)

Se Young Park (Soongsil University, Korea)

Minjae Kim (KIAS, Korea)

Jaeho Han (KAIST)

Kyoo Kim (KAERI, Korea)

Choong Hyun Kim (KIAS, Korea)

Hyeong Jun Lee (KAIST)

Beom Hyun Kim (Seoul National University)

Kyung Min Kim (APCTP)

Kyung-Hwan Jin (JBNU, Korea)

OVERVIEW

Correlated systems, such as transition metal compounds, have been at the forefront of research within the condensed matter physics community. The incompletely filled electron states in the correlated space serve as a source of the rich phenomena observed in these systems. From an electronic structure perspective, the insulating behavior found in transition metal oxides cannot be explained within the framework of a simple band-filling picture. Microscopic approaches, such as the Hubbard model, have been employed as an initial attempt to explain their electronic properties, successfully capturing several key phenomena of correlated systems.

Computational approaches, such as density functional theory (DFT), can complement model-based methods. Notably, these approaches allow us to study real materials rather than simplified models, utilizing non-experimental techniques. DFT has been particularly successful in predicting the ground-state properties of solids, especially for metallic systems. An additional advantage of DFT is that its results can be directly compared with experimental data in a first approximation: for example, the density of states (DOS) can be compared with photoemission spectroscopy (PES) or optical conductivity, band structures with angle-resolved photoemission spectroscopy (ARPES), and calculated magnetic moments or charge data with susceptibility measurements or x-ray absorption spectroscopy (XAS). The true power of DFT emerges when combined with model Hamiltonian (MH) approaches. By extracting the physical parameters of a system, DFT not only identifies the relevant parameters but also provides quantitative estimates of their values, which can be directly utilized in microscopic model studies. The combined methods of DFT and the Hubbard model have been highly successful in numerous studies on transition metal complexes.

Spin-orbit coupling occupies a central role in the study of correlated materials, with both model-based and computational approaches offering critical insights and explanations from their respective perspectives. Complex degrees of freedom, often in conjunction with the dimensional peculiarity, the spin-orbit coupling greatly broadens the phase space one can study. The primary goal of our Advanced Study Group (ASG) is to bring together experts from different computational and model-based communities to foster continuous collaboration and interaction in the field of the correlated transition metal complexes. Each member brings specialized expertise in numerical, analytical, and methodological approaches, which will be synergistically combined to uncover unprecedented explanations of emerging physical phenomena.

Over the years, through a series of ASG activities, we have cultivated constructive collaborations through intensive discussions. In particular, we have actively engaged early-career researchers in the field, involving them in scientific programs and fostering their development. This, we believe, has contributed to the vibrant atmosphere within the broader community beyond ASG and PCS-IBS. Once again, we aim to contribute to the community with our collective enthusiasm and dedication.