Related papers: Multiple-$q$ dipole-quadrupole instability in spin…
Ordering of the frustrated classical Heisenberg model on the triangular-lattice with an incommensurate spiral spin structure is studied under magnetic fields by means of a mean-field analysis and a Monte Carlo simulation. Several types of…
We numerically study orders of planer type $(xy,x^2-y^2)$ quadrupoles on a triangular lattice with nearest-neighbor isotropic $J$ and anisotropic $K$ interactions. This type of quadrupoles possesses unique single-ion anisotropy proportional…
Multipole degrees of freedom describe the mutual interplay among the charge, spin, and orbital degrees of freedom in electrons, which provides a microscopic understanding of unconventional electronic orderings and their associated physical…
We study $\Gamma_3$ quadrupole orders in a face-centered cubic lattice. The $\Gamma_3$ quadrupole moments under cubic symmetry possess a unique cubic invariant in their free energy in the uniform ($q=0$) sector and the triple-q sector for…
Multiple-$Q$ states manifest themselves in a variety of noncollinear and noncoplanar magnetic structures depending on the magnetic interactions and lattice structures. In particular, cubic-lattice systems can host a plethora of multiple-$Q$…
The ordering of the classical Heisenberg model on the pyrochlore lattice with the antiferromagnetic nearest-neighbor interaction J1 and the ferromagnetic next-nearest-neighbour interaction J2 is investigated by means of a mean-field…
Multi-Q magnetic structures on two-dimensional (2D) lattices provide a key route to realizing topological physics in 2D magnetism. A major experimental challenge is to unambiguously confirm their formation by excluding the possibility of…
Noncollinear and noncoplanar magnetic orders lead to unusual electronic structures and transport properties. We here investigate two types of multiple-Q magnetically ordered states and a topological phase transition between them in two…
We theoretically investigate multiple-$Q$ magnetic states emerging from the interference between finite-$Q$ spiral and staggered spin modulations in a one-dimensional itinerant electron system. The multiple-$Q$ spin textures are…
The dynamic phase transitions have been studied, within a mean-field approach, in the kinetic spin-1 Ising model Hamiltonian with arbitrary bilinear and biquadratic pair interactions in the presence of a time varying (sinusoidal) magnetic…
Odd-parity magnetic and magnetic toroidal multipoles in the absence of both spatial-inversion and time-reversal symmetries are sources of multiferroic and nonreciprocal optical phenomena. We investigate electronic states caused by an…
We present microscopic magnetic properties of a two dimensional triangular lattice Sc2Ga2CuO7, consisting of single and double triangular Cu planes. A Curie-Weiss temperature theta_CW = --44 K and an antiferromagnetic (AFM) exchange…
We construct exact ground states of the $J_1$-$J_{3b}$ classical Heisenberg model on the pyrochlore lattice in the presence of a magnetic field. They are non-coplanar multi-$\vec{Q}$ spin configurations with a large magnetic unit cell that…
We investigate multiple-$Q$ instability on a square lattice at particular ordering wave vectors. We find that a superposition of quadruple-$Q$ spin density waves, which are connected by fourfold rotational and mirror symmetries, gives rise…
The results of extensive Monte Carlo simulations of classical spins on the two-dimensional kagome lattice with only dipolar interactions are presented. In addition to revealing the six-fold degenerate ground state, the nature of the…
The triangular-lattice system $\alpha$-RuI$_3$ is isostructural to the widely-studied $\alpha$-RuCl$_3$ compound which was identified as a potential Kitaev system but exhibits, instead of spin liquid behaviour, a magnetically ordered…
Multiple-$Q$ states are expressed as a superposition of spin density waves at multiple ordering wave vectors, which results in unconventional complicated spin textures, such as skyrmion, hedgehog, and vortex. We investigate the multiple-$Q$…
Mott insulators are commonly pictured with electrons localized on lattice sites. Their low-energy degrees of freedom involve spins only. Here we observe emerging charge degrees of freedom in a molecule-based Mott insulator…
We propose novel triple-${\bm q}$ multipole orders as possible candidates for the two distinct low-temperature symmetry broken phases in quadrupolar system PrV$_2$Al$_{20}$. An analysis of the experiment under [111] magnetic fields…
Motivated by recent developments in magnetic materials, frustrated nanoarrays and cold atomic systems, we investigate the behaviour of dipolar spins on the frustrated two-dimensional kagome lattice. By combining the Luttinger-Tisza…