Related papers: Ferromagnetism in Magic-angle Twisted Bilayer Grap…
We study a ferromagnetic tendency in the two-dimensional Hubbard model near van Hove filling by using a functional renormalization-group method. We compute temperature dependences of magnetic susceptibilities including incommensurate…
To elucidate the physics underling magnetism observed in nominally nonmagnetic materials with only $sp$-electrons, we built an extreme model to simulate H-adsorption (in a straight-line form) on graphene. Our first principles calculations…
Motivated by the possible non-spin-singlet superconductivity in the magic-angle twisted trilayer graphene experiment, we investigate the triplet-pairing superconductivity arising from a correlation-induced spin-fermion model on a honeycomb…
We show using extensive simulation results and physical arguments that an Ising system on a two dimensional square lattice, having interactions of random sign between first neighbors and ferromagnetic interactions between second neighbors,…
Thermodynamic properties of cubic Heisenberg ferromagnets with competing exchange interactions are considered near the frustration point where the coefficient $D$ in the spin-wave spectrum $E_{\mathbf{k}}\sim D k^{2}$ vanishes. Within the…
We present the numerical results for low temperature behavior of the transverse-field Ising model on a frustrated checkerboard lattice, with focus on the effect of both quantum and thermal fluctuations. Applying the recently-developed…
Magic-angle twisted trilayer graphene (MATTG) recently exhibited robust superconductivity at a higher transition temperature (TC) than the bilayer version. With electric gating from both the top and bottom sides, the superconductivity was…
The magnetic and entanglement thermal (equilibrium) properties in spin-1/2 Ising-Heisenberg model on a triangulated Kagome lattice are analyzed by means of variational mean-field like treatment based on Gibbs-Bogoliubov inequality. Because…
The electronic properties of bilayer graphene strongly depend on relative orientation of the two atomic lattices. Whereas Bernal-stacked graphene is most commonly studied, a rotational mismatch between layers opens up a whole new field of…
Mixed spin-1/2 and spin-1 Ising ferrimagnets on a triangular lattice with sublattices A, B and C are studied for two spin value distributions $(S_{\rm A},S_{\rm B},S_{\rm C})=(1/2,1/2,1)$ and $(1/2,1,1)$ by Monte Carlo simulations. The…
The conditions for spontaneous magnetization in a single graphene sheet are discussed in the context of Mermin-Wagner theorem. It is rigorously proved that at any nonzero temperature the graphene monolayer is nonmagnetic as long as its…
We present Monte Carlo and Langevin micromagnetic calculations to investigate thermal switching of single-domain ferromagnetic particles. For the Monte Carlo study we place particular emphasis on the probability that the magnetization does…
Binary magnetic square lattice Ising system with nearest neighbour interactions were simulated using the Monte Carlo technique. Two types of ions were randomly distributed on the lattice sites, one type interacting ferromagnetic and the…
We present a detailed study of the emergence of bulk ferromagnetism in low carrier density samples of undoped indium tin oxide (ITO). We used annealing to increase the density of oxygen vacancies and change sample morphology without…
The discovery of superconductivity in twisted bilayer and twisted trilayer graphene has generated tremendous interest. The key feature of these systems is an interplay between interlayer coupling and a moir\'e superlattice that gives rise…
The conditions under which ferromagnetism may occur in transition metal oxides with partially filled $t_{2g}$ shells such as vanadium-based perovskites are studied using a combination of density functional and single-site dynamical mean…
The magnetic properties of the ferromagnetic-ferromagnetic-antiferromagnetic trimerized spin-1/2 Heisenberg chain are studied theoretically. The high temperature susceptibilty and the ground state saturation magnetic field are calculated…
We investigate the magnetic properties of spin-$1/2$ charged Fermi gases with ferromagnetic coupling via mean-field theory, and find the interplay among the paramagnetism, diamagnetism and ferromagnetism. Paramagnetism and diamagnetism…
Moire systems offer an exciting playground to study many-body effects of strongly correlated electrons in regimes that are not easily accessible in conventional material settings. Motivated by a recent experiment on…
Superconductivity often occurs close to broken-symmetry parent states and is especially common in doped magnetic insulators. When twisted close to a magic relative orientation angle near 1 degree, bilayer graphene has flat moire…