Single Crystal Growth And Physical Properties Of Magnetically Doped Sb-Te Binary Compounds

Topological materials,as a new type of quantum functional materials,have received more and more attention in recent years,and have been widely studied,such as topological insulators,Weyl semimetals,etc.Some novel physical phenomena have also been found in the magnetic doping of such materials and have been used in the study of condensed matter physics.For example,the topological insulator with an insulating bulk state inside and a metallic surface state has a completely polarized spin and a topological surface state protected by time inversion symmetry,which makes it be an ideal material for the study of spintronics.In addition,magnetic-doped topological materials are more easier to have intrinsic ferromagnetism,this is important for undermining its time reversal symmetry,opening the surface state band,observing anomalous hall effect?AHE?,and then achieving anomalous quantum hall effect?QAHE?,it also provides ideal materials for studying novel physical phenomena and implementing surface state without energy consumption.In recent years,there have been extensive studies on Sb-Te binary compound systems in topological materials,including magnetic-doped Sb₂Te₃ and Sb₂Te,but there are few reports on the single crystal growth of Sb₄Te₃ and the basic physical properties of magnetic-doped Sb₄Te₃.In this paper,high quality single crystal growth of several magnetic-doped Sb-Te binary compounds was directly synthesized by the slow cooling method,and the structure characterization of the single crystal growth and the study of magnetic and electrical transport properties were carried out.The related work mainly includes:1.First,a high-quality Sb_4-xCr_xTe₃ monocrystal sample was successfully obtained by changing the synthetic material and exploring the growth process.By means of XRD,EDX and other structural characterization methods,Sb:Te=4:3was determined in the obtained crystal sample.The magnetic and electrical transport properties of the obtained single crystal samples were tested.The data analysis shows that the highest Curie temperature Tc=7 K is obtained when x=0.04,and the anomalous hall effect?AHE?is found in the measurement of hall resistance at this concentration,which directly proves that the ferromagnetic state in the sample is intrinsic and not caused by magnetic element impurities.The measurement of hall resistance also shows that the dominant carrier is hole,and the hole concentration increases with the increase of sample doping concentration.2.The single crystal growth,phase and magnetism of Sb_2-xMn_xTe and Sb_2-xV_xTe were studied and analyzed.The results of magnetic measurement showed that weak ferromagnetic signals were found in the samples doped with Mn and V,and no obvious ferromagnetic transformation appeared due to the influence of doping concentration and growth conditions.