| In recent years,the quantum Hall effect,two-dimensional superconductivity and other strange transport properties observed in two-dimensional?2D?materials represented by graphene have caused a research upsurge in two-dimensional materials.Recently,in layered transition metal sulfides?TMDCs?,Weyl fermions of the second kind caused by their special crystal structure and strong spin-orbit coupling have attracted more and more attention in the field of physics.Especially with the progress of sample preparation technology,people have recently realized quantum anomalous Hall effect in single layer WTe2,giant magnetoresistance effect in single layer molybdenum disulfide?MoS2?by ferromagnetic gate electrode regulation,and room temperature ferromagnetism in single layer VS2.These works have laid a foundation for studying the application of low-layer transition metal sulfides in spintronics.However,at present,these single-layer transition metal sulfides are all obtained through complicated mechanical cleavage processes and involve a multi-step sample transfer process,which greatly limits the research progress of people.Therefore,it is necessary to find a new way to obtain two-dimensional ferromagnetic materials more easily.Based on this,high quality FeS2 samples with few layers were grown by chemical vapor deposition?CVD?.The samples were characterized by high-resolution transmission electron microscope?HETEM?,Raman Spectra,X-ray photoelectron spectroscopy?XPS?and other means,which proved that it was the FeS2 structure of 2H phase.In order to characterize the basic ferromagnetic properties,we have prepared devices using micro-nano processing equipment.By measuring the low-temperature electrical transport properties,we have observed the obvious hysteresis behavior of magnetoresistance under the low-temperature strong magnetic field,indicating that ferromagnetism may exist in the samples.Furthermore,we measured the magnetization curve of the sample by vibrating sample magnetometer?VSM?. |
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