SmCo(1-x)IrxAsO体系的磁性和输运性质  

Magnetic and transport properties in SmCo_(1-x)Ir_xAsO

作　　者：苏春燕[1] 陈永亮[2] 崔雅静[2] 赵勇[2] 

机构地区：[1]武夷学院机电工程学院,武夷山354300 [2]磁浮技术与磁浮列车教育部重点实验室,超导与新能源研究开发中心,西南交通大学,成都610031

出　　处：《低温与超导》2016年第1期28-32,共5页Cryogenics and Superconductivity

摘　　要：采用固相反应法,制备出一系列SmCo1-xIrxAsO(x=0.05,0.1,0.15,0.2,0.25,0.3)多晶样品。XRD测试结果表明所有样品均具有ZrCuSiAs型四方结构,随着掺杂量的增加,晶格参数a变大,c变小。在x≥0.25时发现小部分杂相峰IrAs2,说明SmCo1-xIrxAsO体系单相样品较难制得。磁性测量结果表明,SmCo1-xIrxAsO在高温区表现出顺磁性。外场为10Oe时,掺杂量为0.05的样品随着温度的降低,依次在60K和45K附近出现铁磁转变和反铁磁转变,在低温区ZFC与FC曲线分离,出现明显的不可逆性。随着外磁场的增加,不可逆性受到抑制,铁磁转变温度TC向高温方向移动。增加掺杂量,样品铁磁反铁磁转变温度几乎不变,表明Ir掺杂对样品磁性没有影响。M-H曲线表明,温度T<30K时,所有掺杂样品随着磁场的增加,均出现反铁磁(AFM)-铁磁(FM)的磁性转变,且转变磁场随温度的升高而减小。T=50K时,这种变磁性转变消失,样品表现出软铁磁特性。A series of polycrystalline sample SmCo1-x Irx AsO （ x = 0. 05,0.1,0.15,0.2,0.25,0.3 ） was prepared by solid - state reaction method . X - ray diffraction patterns indicate that all the samples formed the ZrCuSiAs - type structure. The increa- ses of the lattice constant a and decreases of c were observed with increased amount of doping. Small part of impurity peak IrAs2 was found when x≥0.25 ,indicated that SmCol _xIrxAsO system was difficult to prepare single -phase samples. Magnetic meas- urement results show that SmCo1-xIrxAsO exhibits paramagnetism. As the temperature decreases, ferromagnetic transition and anti- ferromagnetic transition are found in the vicinity of 60K and 45K. for sample of x = 0. 05 when the applied field is 10 Oe. At low temperature zone, the ZFC and FC curve separated, showing strong irreversibility. With the increase of temperature, irreversibility of SmCo1-xIr, AsO was suppressed, and the ferromagnetic transition temperature Tc toward the direction of high temperature. As the doping level increases, temperature of FM and AFM never change,indicating that doping amount of Ir doesn＇ t influence sam- pies＇ magnetism. M - H curves show that magnetic transition from antiferromagnetic to ferromagnetic was occurred with increasing magnetic field when temperature T 〈 30K,and the change of magnetic field decreases when the temperature increased. As T = 5OK, sample metamagnetic transition disappears, instead exhibiting soft magnetic properties.

关 键 词：SmCoAsO Ir掺杂 磁性质 

分 类 号：TM262[一般工业技术—材料科学与工程]