This paper reviews experimental evidence and the related theoretical background on exotic
phenomena arising from local quadrupolar degrees of freedom. Recent extensive studies on …

Over the past 35 years, research on unconventional superconductivity in heavy-fermion
systems has evolved from the surprising observations of unprecedented superconducting …

The coexistence and competition between superconductivity and electronic orders, such as
spin or charge density waves, have been a central issue in high transition-temperature (T c) …

The multipole moment is an established concept of electrons in solids. Entanglement of spin,
orbital, and sublattice degrees of freedom is described by the multipole moment, and …

PrV 2 Al 20 is a rare example of a heavy-fermion system based on strong hybridization
between conduction electrons and nonmagnetic quadrupolar moments of the cubic Γ 3 …

The combined rotational and time-reversal symmetry breakings that define an altermagnet
lead to an unusual d-wave (or g-wave) magnetization order parameter, which in turn can be …

Multipolar spin systems provide a rich ground for the emergence of unexpected states of
matter due to their enlarged spin degree of freedom. In this study, with a specific emphasis …

Superconductors with exotic physical properties are critical to current and future technology.
In this review, we highlight several important superconducting families and focus on their …

The multipole concept, which characterizes the spacial distribution of scalar and vector
objects by their angular dependence, has already become widely used in various areas of …

The origin of the nonmagnetic phase transition in PrTi 2 Al 20, reported earlier in a
macroscopic study, has been asserted microscopically using elastic and inelastic neutron …