Theory Study On Thermodynamic Properties,Polarization And Magnetization Properties Of Ferroelectric/ferromagnetic Chain

Multiferroic materials can be divided into two types:single phase multiferroic materials and multiferroic composite materials.The latter one has attracted great attention recently owing to considerable magnitude of magnetoelectric effect and can be produced by man.In this paper focus on dynamic continuous model,which is used to describe ferroelectric/ferromagnetic composites materials under the approximate discretization,using the transfer matrix method to calculate the thermodynamic properties and electric polarization properties of ferroelectric part,calculating the thermodynamic properties and magnetic properties of ferromagnetic part,The conclusions are as follow.(1)One-dimensional ferroelectric system:There is no spontaneous polarization on system,and producing polarization at electric field,polarization increases with the increase of electric field intensity and temperature,energy increases with the increase of temperature,but after reaching a certain temperature,increasing rate decreases.Specific heat increase with the increase of temperature from scratch,then Specific heat drops rapidly after reaching an extreme value.When there is no electric field polarization monotone decreasing,and the rate of change is very big at low temperature,and the rate of change is small at high temperature.Polarization curve shows polarization is zero when electric field is zero,there is no electric hysteresis phenomenon.(2)One-dimensional ferromagnetic system:There is no spontaneous magnetization on system,and producing magnetization at magnetic field,magnetization increases with the increase of magnetic field intensity and temperature,energy increases with the increase of temperature,but after reaching a certain temperature,increasing rate decreases.Specific heat increase with the increase of temperature from scratch,then Specific heat drops rapidly after reaching an extreme value.When there is no magnetic field magnetization monotone decreasing,and the rate of change is small at high temperature.magnetization has a extremum near a certain temperature when tere is an magnetic field.magnetization is zero when magnetic field is zero,there is no magnetic hysteresis phenomenon.(3)One-dimensional ferroelectric/ferromagnetic system:the total internal energy of Ferroelectric/ferromagnetic system increases with the increase of temperature,Internal energy tends to be stable after the temperature get a certain value.Transition temperature of system of ferromagnetic relates to magnetic anisotropy effect and ferroelectric fourth power function.Transition temperature will rise with the increase of magnetic anisotropy,Peak of transition temperature reduce with increasing of ferroelectric fourth power function.Due to magnetic susceptibility of the system only dependent on ferromagnetic part and polarizability of system is only related to system ferroelectric part,so the total magnetic susceptibility and polarizability is equal to the polarizability of ferroelectric part and magnetisability is equal to magnetisability of magnetic part.magnetization and polarization of Interface increase with increasing of the electric field,magnetic field intensity and the interface layer interaction.