Magnetic Properties of a Layer Film With a Honeycomb Lattice

A molecular-based magnetic material is abstracted as a layer film with a honeycomb lattice. Based on the combination method of the linear spin-wave approximation and the retarded Green´s function, the magnetic properties of the system have been studied in detail. The expressions of magnetization and spin-wave spectrum in the system are given. The emphasis is on the effects of the spin and the anisotropy on the spin-wave spectra, the energy gap, the magnetization, and the quantum fluctuation. The numerical results show that the spin-wave spectrum only has an acoustic branch for the case of spin values equal without the anisotropy. On the contrary, the spin-wave spectrum shows an optical branch when the spin values are not equal to or with the anisotropy. The anisotropy plays an important role in the energy gap, the magnetization, and the quantum fluctuation of the system. Some interesting results may provide great help in the structure design of new molecular-based magnetic materials.