Related papers: Doping a spin-one Mott insulator: possible applica…
In this paper we explore possible phases arising from doping neutral excitons into a Mott insulator in the context of moir\'e bilayers. We consider two moir\'e layers coupled together only through inter-layer repulsion and there is a…
Possible superconductivity in recently discovered (Tl,K)Fe$_x$Se$_2$ compounds is studied from the viewpoint of doped Mott insulator. The Mott insulating phase is examined to be preferred in the parent compound at $x=1.5$ due to the…
Motivated by recent experiments on the quantum-spin-liquid candidate material LiZn2Mo3O8, we study a single-band extended Hubbard model on an anisotropic Kagome lattice with the 1/6 electron filling. Due to the partial filling of the…
We study two types of models for the superconducting layered nitride $\beta$-MNCl(M=Hf,Zr); a single band model on a triangular lattice, and a two band model on a honeycomb lattice. We find that the former model does not suffice as an…
High temperature superconductivity was recently found in the bilayer nickelate $\rm{La}_3 \rm{Ni}_2 \rm{O}_7$ (La327), followed by the discovery of superconductivity in the trilayer $\rm{La}_4 \rm{Ni}_3 \rm{O}_{10}$ (La4310), under high…
Recently, signatures of superconductivity with critical temperature from 20 to 30 K have been reported in pressured trilayer nickelate La$_4$Ni$_3$O$_{10}$ through a pressure-induced structure transition. Here we explore the evolution of…
The newly discovered Ruddlesden-Popper bilayer La$_3$Ni$_2$O$_7$ reaches an remarkable superconducting transition temperature $T_c$ = 80 K under a pressure of above 14 GPa. Here we propose a minimal bilayer two-orbital model of the…
Superconductivity in nickelates apparently takes place in two different Ni oxidation regimes, namely either for infinite-layer-type compounds close to Ni$^{+}$, or for Ruddlesden-Popper materials close to Ni$^{2+}$. The reduced…
Motivated by the discovery of superconductivity in bilayer La$_3$Ni$_2$O$_7$ at 80 K and the increased superconducting transition temperature, $T_\text{c}$, up to 92 K in single crystals of La$_2$SmNi$_2$O$_7$ under pressure, we…
The recent discovery of high-$T_{c}$ superconductivity in bilayer nickelate La$_{3}$Ni$_{2}$O$_{7}$ under high pressure has stimulated great interest concerning its pairing mechanism. We argue that the weak coupling model from the almost…
Understanding how superconductivity emerges and collapses in correlated electron systems remains a central challenge in condensed matter physics. As a recently discovered member of the high temperature superconductor family, bilayer…
The discovery of high-${T_c}$ superconductivity in pressurized bilayer nickelate La$_3$Ni$_2$O$_7$ presents a new arena for exploring unconventional pairing mechanisms. A pivotal yet unresolved issue is the specific role of the $3d_{z^{2}}$…
The study of non-s-wave unconventional superconductivities in strongly correlated-electron systems has been a central issue in condensed matter physics for more than 30 years. In such unconventional superconductivities, d-wave Cooper…
Whether the newly discovered KxFe2-ySe2 systems are doped Mott or band insulators is key to how superconductivity emerges at lower temperature. With extant theoretical studies supporting conflicting scenarios, a more realistic approach is…
High-temperature superconductors at zero doping can be considered strongly correlated two-dimensional Mott insulators. The understanding of the connection between the superconductor and the Mott insulator hits at the heart of the…
Using the continuum model for low energy non-interacting electronic structure of moir\'e van der Waals heterostructures developed by Bistritzer and MacDonald [1], we study the competition between spin, charge, and superconducting order in…
The recent and exciting discovery of superconductivity in the hole-doped infinite-layer nickelate Nd 1-{\delta} Sr {\delta} NiO 2 draws strong attention to correlated quantum materials. From a theoretical view point, this new class of…
The discovery of nickelate superconductivity provided the first example of a non-copper-based material with superconductivity strongly analogous to the cuprates, but recent findings raise questions and inconsistencies around the electron…
Inspired by recent discovery of correlated insulating states in twisted bilayer graphene (TBG), we study a two-orbital Hubbard model on the honeycomb lattice with two electrons per unit cell. Based on the real-space density matrix…
The discovery of superconductivity in nickelate compounds has opened new avenues in the study of high-temperature superconductors. Here we provide a comprehensive overview of recent progress in the field, including all different nickelate…