Magnetic And Electric Field Control Of Multiferroic TmCrO₃ Films

Since the 21st century,the amount of information in the world has exploded,and the demand for low-energy consumption,high-density,fast-reading and writing memory devices has become more urgent.In view of the characteristics of ferroelectric storage being easy to write and magnetic storage being easy to read,multiferroic materials provide the possibility for the realization of"electrical writing/magnetic reading"type of high-performance memory.In this paper,single-phase multiferroic material TmCrO₃is taken as the research object,and the magnetic property and electronically controlled magnetic behaviors are studied.The main research results are as follows:1.The TmCr_1-xFe_xO₃bulk was prepared by traditional solid-phase method,and its magnetic property and electronically controlled magnetism were measured using an physical property measurement system.It is found that TmCr_1-xFe_xO₃exhibited antiferromagnetic phase transition for x=0-0.3,and T_Nincreases with the increasing of doping content x.Such change can be attributed to the increase of Cr/Fe-O（4c）-Cr/Fe angle after Fe doping,which stabilizes the noncollinear spin structure of Cr/Fe sublattice and enhances the superexchange interaction.Magnetization reversal was observed for x=0-0.3,and the compensation temperature T_compincreases with the increasing of x.This is due to the decrease of M_Cr/Feas x increases.In TmCr_1-xFe_xO₃,exchange bias phenomenon is observed when x=0-0.3,which originates from the antiferromagnetic coupling between Cr/Fe³⁺and Tm³⁺.Further research found that the magnetization of TmCrO₃increases under the action of the electric field,indicating that the electric field can regulate the magnetic properties of TmCrO₃,which can be attributed to the existence of magnetoelectric coupling in the system.2.TmCrO₃films were grown on SrTiO₃single crystal substrates using a pulsed laser deposition system,and high-quality oriented TmCrO₃films were obtained by regulating different preparation conditions（deposition temperature,deposition time,etc.）.The study found that with the increase of deposition temperature,the grain size of the TmCrO₃film gradually became uniform and the roughness became smaller,and its saturation magnetization gradually increases with the increase of deposition temperature.By comparing the films with different deposition time,it is found that the saturation magnetization for 50 nm is greater than that for 100 nm,which is due to the worse orientation of the film for 100 nm.In addition,it was found that the electric field can also regulate the saturation magnetization of the TmCrO₃film,similar to TmCrO₃bulk,which can be attributed to magnetoelectric coupling.