Strongly interacting quantum many-body states can be mapped to noninteracting quantum states, enabling a new quantum neural network called the Fermi machine to solve strongly correlated electron problems.

The correspondence principle states that as quantum numbers approach infinity, the nature of a system described by quantum mechanics should match that described by classical mechanics. Quantum phenomena, such as quantum superposition and quantum correlation, generally become unobservable when a system approaches this regime. Conversely, as quantum numbers decrease, classical descriptions give way to observable quantum effects. The external approach to classical–quantum crossover has attracted research interest. This study aims to demonstrate a method for achieving such control in materials.

Based on the charge disproportionation of V³⁺ and V²⁺, the V³⁺(d²) trimers and V²⁺(d³) tetramers in the vanadium pyrochlore lattice of AlV₂O₄ are described by the orbitally-induced Peierls mechanism.

Using first-principles calculations, we evaluated the exchange stiffness constants of ferromagnetic metals at finite temperatures. The constants can be used as parameters in the Landau–Lifshitz–Gilbert equation.

A new superconductor family, Sc₆MTe₂, has been discovered, comprising seven variations with magnetic elements labeled as M. Notably, only a few known superconductor families exist that involve various magnetic elements.

A collection of papers in the Journal of the Physical Society of Japan advances our understanding of Dzyaloshinskii–Moriya interaction and paves the way for developing next generation computing and electronic systems.

A new review discusses the high-temperature superconductivity mechanisms in copper oxides, explaining the various phases observed in these materials based on a nonperturbative effect called self-energy singularity.

A Special Topics edition of the Journal of the Physical Society of Japan features articles discussing recent advancements in hyperordered structures in materials, their applications, and the techniques for observing them.

The Journal of the Physical Society of Japan highlights in this special topic recent advances in modern physics that have been realized with the generation of pulsed high magnetic fields.

The topology of Fermi surfaces with heavy effective masses in strongly correlated topological superconductor UTe₂ was investigated using quantum oscillation measurements and theoretical calculations.

“The energy level of an electron state increases as the number of nodes in its wave function increases.” The preceding statement, often found in textbooks, was challenged by our large-scale DFT (density-functional theory) calculations performed for the decavacancy in Si crystal.

A black-phosphorus-derived Zintl compound, MoP₄, is obtained by high-pressure synthesis. The material exhibits a non-quadratic large magnetoresistance and semi-metallic Seebeck behavior, as predicted by the first principles calculations yielding massive and non-symmorphic Dirac semimetal states.

A high-quality single crystal of rhenium oxide shows significantly large magnetoresistance, potentially originating from a unique electronic structure called “hourglass Dirac chain” protected by the symmetry of the crystal.

Scientists demonstrate the presence of non-Hermitian topological properties preserved under continuous physical deformations in strongly correlated systems in equilibrium, resulting from short-lived quanta of collective excitations.

While quantum systems are traditionally described by Hermitian Hamiltonians, the formalism is extendable to a non-Hermitian description for systems that are dissipative or obey parity-time symmetry.

Order parameter of non-magnetic phase transition at 105 K, which is called "hidden order", was revealed in spin-orbit coupled iridate Ca₅Ir₃O₁₂. This discover of order parameter with rotational and directional degrees of freedom in atomic scale will lead to development of energy saving devices with a fast cross-correlated response.

An international team of researchers reviews the research progress on strongly spin-orbit coupled systems, providing an overview of theoretically predicted electronic phases, candidate materials, and unusual experimental observations.

Using an organic massless Dirac fermion system, we found that massless Dirac fermions undergo a quantum phase transition without creating any mass gap even in the strong coupling regime.