Related papers: Interplay between multipolar spin interactions, Ja…
In the development of spin-based electronic devices, a particular challenge is the manipulation of the magnetic state with high speed and low power consumption. Although research has focused on the current-induced spin-orbit torque based on…
We study the effect of spin-phonon coupling in small magnetic clusters, concentrating on a S=1/2 ring of 4 spins coupled antiferromagnetically. If the phonons are treated as classical variables, there is a critical value of the spin-phonon…
Zintl phases, containing strongly covalently bonded frameworks with separate ionically bonded ions, have emerged as a critical materials family in which to couple magnetism and strong spin-orbit coupling to drive diverse topological phases…
We discuss Mott insulating and metallic phases of a model with $e_g$ orbital degeneracy to understand physics of Mn perovskite compounds. Quantum Monte Carlo and Lanczos diagonalization results are discussed in this model. To reproduce…
The zero-temperature phase diagram of the spin-$\frac{1}{2}$ $J_{1}$--$J_{2}$--$J_{1}^{\perp}$ model on an $AA$-stacked square-lattice bilayer is studied using the coupled cluster method implemented to very high orders. Both…
It is demonstrated that there is anti-ferromagnetic spin-spin interaction between nearest electrons in the 2D Wigner crystal. This is also valid for the Wigner liquid - the state with destroyed long-range order but preserved short-range…
We report on the experimental characterization of various types of spin-exchange interactions between two individual atoms, where pseudo-spin degrees of freedom are encoded in different Rydberg states. For the case of the direct…
Motivated by the recent activities on the Ni-based diamond lattice antiferromagnet NiRh$_2$O$_4$, we theoretically explore on a general ground the unique spin and orbital physics for the Ni$^{2+}$ ions with a $3d^8$ electron configuration…
The zero-temperature phase diagram of the frustrated spin-$\frac{1}{2}$ $J_{1}$--$J_{2}$--$J_{1}^{\perp}$ Heisenberg magnet on an $AA$-stacked honeycomb bilayer lattice is studied using the coupled cluster method implemented to very high…
First-principles calculations reveal a large cooperative coupling of Jahn-Teller (JT) distortion to oxygen-octahedron rotations in perovskite LaMnO$_3$. The combination of the two distortions is responsible for stabilizing the strongly…
We perform charge density functional theory plus $U$ calculation of LaMnO$_3$. While all the previous calculations were based on spin density functionals, our result and analysis show that the use of spin-unpolarized charge-only density is…
We derive an effective Hamiltonian that takes into account the quantum nature of phonons and models cooperative Jahn-Teller effect in the adiabatic regime and at strong electron-phonon coupling in one dimension. Our approach involves…
Dynamical Jahn-Teller (DJT) effect in a spin-orbital coupled system on a honeycomb lattice is examined, motivated from recently observed spin-liquid behavior in Ba$_3$CuSb$_2$O$_9$. An effective vibronic Hamiltonian, where the superexchange…
We demonstrate multiferroic behavior in trimerized Mott insulators through interplay between spins and electric dipole moments resulting from electronic charge fluctuations in frustrated units. The model consists of stacked triangular…
We examine the effect of small amounts of magnetic substituents in the $A$ sites of the frustrated spinels MgCr$_2$O$_4$ and ZnCr$_2$O$_4$. Specifically we look for the effects of spin and lattice disorder on structural changes accompanying…
Despite serious effort, the nature of the magnetic interactions and the role of electron-correlation effects in magnetic two-dimensional (2D) van der Waals materials remain elusive. Using CrI$_3$ as a model system, we show that the…
We present results of local spin density approximation pseudopotential calculations for the ferroelectromagnet, yttrium manganite (YMnO3). The origin of the differences between ferroelectric and non-ferroelectric perovskite manganites is…
As a hallmark of electronic correlation, spin-charge interplay underlies many emergent phenomena in doped Mott insulators, such as high-temperature superconductivity, whereas the half-filled parent state is usually electronically frozen…
A spin Hamiltonian, which characterizes interatomic interactions between spin moments, is highly valuable in predicting and comprehending the magnetic properties of materials. A deeper understanding of the microscopic origin of magnetic…
We study the effects of magneto-elastic coupling on the degenerate ground state of the antiferromagnetic Heisenberg model on regular triangle and tetrahedron clusters of spin-1/2. Both give very similar results. Static distortion lifts the…