六方相反铁磁材料Mn_(3)Ge的交换偏置效应

Exchange Bias Effect of Hexagonal Antiferromagnetic Material Mn_(3)Ge

交换偏置效应对于微型磁存储器件中稳定的磁畴结构具有重要的作用,研究在室温下仍具有交换偏置效应的材料对于新一代自旋电子器件具有重要意义。采用助熔剂法成功合成Mn_(3)Ge晶体。利用X射线衍射仪(XRD)和能量色散X射线光谱仪(EDS)对材料进行了表征,并利用磁学性质测量系统(MPMS)进行了磁学性质测试。磁化曲线显示在5×10^(4) Oe(1A·m^(-1)=4π×10^(-3) Oe)磁场冷却下,温度为2K时Mn_(3)Ge的交换偏置场强度为6400Oe,温度为300K时Mn_(3)Ge的交换偏置场强度为360Oe,说明这种反铁磁材料在室温磁存储器件应用领域具有极大潜力。在5×10^(4) Oe磁场冷却下定温循环测量的磁滞回线有明显偏移,表明材料中存在锻炼效应,从而进一步验证交换偏置效应是一种本征行为。

Exchange bias effect plays an important role in the stable magnetic domain structure of micro magnetic storage devices.It is of great significance to study materials with exchange bias effect at room temperature for a new generation of spintronic devices.MnGe crystal was successfully synthesized by flux method.The materials were characterized by the X-ray diffractometer(XRD)and energy dispersive X-ray spectrometer(EDS),and the magnetic properties were tested by the magnetic property measurement system(MPMS).The magnetization curve shows that under 5×10^(4) Oe(1 A·m=4π×10Oe)magnetic field cooling,the exchange bias field intensity of MnGe is 6400 Oe at 2 K,and the exchange bias field intensity of MnGe is 360 Oe at 300 K,indicating the great potential of the antiferromagnetic material in the application field of magnetic storage devices at room temperature.The hysteresis loop measured by constant temperature cycling under 5×10^(4) Oe magnetic field cooling has obvious deviation,indicating that there is training effect in the material,and further verifying that the exchange bias effect is an intrinsic behavior.