Related papers: The ferromagnetic order in graphene
Magnetic properties of graphene with randomly distributed magnetic defects/vacancies are studied in terms of the Kondo Hamiltonian in the mean field approximation. It has been shown that graphene with defects undergoes a magnetic phase…
Antiferromagnets (AFMs) exhibit intrinsic magnetization when the order parameter spatially varies. This intrinsic spin is present even at equilibrium and can be interpreted as a twisting of the homogeneous AFM into a state with a finite…
The electronic structure, bonding and magnetism in graphene containing vacancies are studied using density-functional methods. The single-vacancy graphene ground state is spin polarized and structurally flat. The unpolarized state is non…
We study the spin-wave excitations near the zigzag edge of graphene. It is rather interesting that we obtain a single branch of relativistic ferromagnetic magnon due to the presence of the open boundary. Note that magnons in antiferomagnets…
Measurement of magnetic oscillations on thermodynamic quantities (like magnetization and specific heat), is one of the experimental methods to access the density of states of electronic systems. In the present paper we therefore…
It is shown that a strong impurity potential induces short-range antiferromagnetic (ferrimagnetic) order around itself in a Hubbard model on a half-filled honeycomb lattice. This implies that short-range magnetic order is induced in…
Atomically thin magnets are the key element to build up spintronics based on two-dimensional materials. The surface nature of two-dimensional ferromagnet opens up opportunities to improve the device performance efficiently. Here, we report…
The paper presents the author view on spin-rooted properties of graphene supported by numerous experimental and calculation evidences. Dirac fermions of crystalline graphene and local spins of graphene molecules are suggested to meet a…
We investigate a competition of tendencies towards ferromagnetic and incommensurate order in two-dimensional fermionic systems within functional renormalization group technique using temperature as a scale parameter. We assume that the…
Orbital magnetism is studied for graphene flakes with various shapes and edge configurations using the tight-binding approximation. In the low-temperature regime where the thermal energy is much smaller than to the energy level spacing, the…
Exact analytic solutions for an electron in graphene interacting with external complex magnetic fields are found. The eigenvalue problem for the non-hermitian Dirac-Weyl Hamiltonian leads to a pair of intertwined Schr{\"o}dinger equations,…
Spontaneous symmetry breaking phenomena in the transverse field mixed $p$-spin glass model in finite dimensions are studied with Nishimori's gauge theory. Useful identities in the gauge theory enable us to study $\mathbb Z_2$-symmetry…
The elementary excitations from the conventional magnetic ordered states, such as ferromagnets and antiferromagnets, are magnons. Here, we elaborate a case where the well-defined magnons are absent completely and the spin excitation spectra…
The arguments supporting the existence of the intrinsic magnetism in carbon-based materials including pure graphene were analyzed critically together with the numerous experimental evidences denying the magnetism in these materials. The…
General phenomenological theory of magnetic spin waves in ferromagnetic media is originally reformulated and applied to analysis of magnetostatic waves in films and plates with arbitrary nisotropy under arbitrary external field. Exact…
We have measured the magnetic field and temperature dependence of the resistivity of several micrometers long and heterogeneously thick graphite sample. The magnetoresistance results for fields applied nearly parallel to the graphene planes…
Nonlinear dynamics govern a wide array of natural phenomena and are essential for understanding nonequilibrium behaviors in condensed matter systems. In magnetically ordered materials, magnons - the quanta of spin waves - exhibit intrinsic…
In this paper, we present the solutions of the Dirac-Weyl equation for graphene under a constant magnetic field. The resulting spectrum is used to determine the partition function, a key quantity in the study of thermodynamic properties.…
Linear and angular momenta of a soliton in a ferromagnet are commonly derived through the application of Noether's theorem. We show that these quantities exhibit unphysical behavior: they depend on the choice of a gauge potential in the…
In this paper we consider the phonons in monolayer graphene and we show the possibility for the spin-triplet superconducting excitations states by discretizing the single-particle excitations near Fermi wave vector. The molonayer graphene…