The repulsive Hubbard model has been immensely useful in understanding strongly
correlated electron systems and serves as the paradigmatic model of the field. Despite its …

The Hubbard model is the simplest model of interacting fermions on a lattice and is of similar
importance to correlated electron physics as the Ising model is to statistical mechanics or the …

The first-principles band theory paradigm has been a key player not only in the process of
discovering new classes of topologically interesting materials, but also for identifying salient …

Open quantum systems (OQSs) cannot always be described with the Markov approximation,
which requires a large separation of system and environment time scales. An overview is …

A review of the basic ideas and techniques of the spectral density-functional theory is
presented. This method is currently used for electronic structure calculations of strongly …

Quantum impurity models describe an atom or molecule embedded in a host material with
which it can exchange electrons. They are basic to nanoscience as representations of …

Atomic clusters, consisting of a few to a few thousand atoms, have emerged over the past 40
years as the ultimate nanoparticles, whose structure and properties can be controlled one …

We discuss phenomena arising from the combined influence of electron correlation and spin-
orbit coupling (SOC), with an emphasis on emergent quantum phases and transitions in …

In the early 1970s, Wilson developed the concept of a fully nonperturbative renormalization
group transformation. When applied to the Kondo problem, this numerical renormalization …

The recent discovery of superconductivity in La 3 Ni 2 O 7 with T c≃ 80 K under high
pressure opens up a new route to high-T c superconductivity. This material realizes a bilayer …