CuGe_(1-x)Ga_xO_3的低温磁性质  

LOW TEMPERATURE MAGNETIC PROPERTIES OF CuGe_(1-x) Ga_xO_3

作　　者：杨宏顺[1] 王宇行[1] 李鹏程[1] 柴一晟[1] 侯碧辉[1] 曹烈兆[2] 

机构地区：[1]中国科学技术大学物理系,合肥230026 [2]中国科学技术大学结构分析开放实验室,合肥230026

出　　处：《物理学报》2001年第1期126-131,共6页Acta Physica Sinica

基　　金：国家重点基础研究专项经费 (批准号 :19990 6 46 )资助的课题&&

摘　　要：制备了单相性很好的CuGaxGe1-xO3(x =0 ,0 .0 1)多晶样品 ,在不同磁场下对其低温磁化率进行了测量 .Ga的掺杂所产生的O空穴导致CuO6八面体的畸变 ,使b轴的晶格参数变小 .Ga掺杂抑制了Spin Peierls相变的温度并使自旋单态 三重态之间的能隙减小 .磁场对能隙有抑制作用 ,同时使参与Spin Peierls相变的Cu2 +离子数减少 ,另一方面 ,磁场能增加不参与双聚化的Cu2 +(即Cu2 +自由自旋 )的数目 .The polycrystalline samples of single-phase CuGaxGe1-xO3 (x = 0,0.01) are synthesized. Their low-temperature magnetic susceptibility are measured under different magnetic fields. The oxygen holes generated by Ga doping induce the distortion of the CuO6 octahedron, and cause b axis of the crystal lattice to become shorter. Ga doping decreases the spin-Peierls transition temperature and also the energy gap between the spin singlet-state and the triplet-state. The magnetic fields have the effectiveness of inhibiting the energy gap, meanwhile, reducing the spin number of Cu2+ ions that are involved in the spin-Peierls phase transition. On the other hand, the magnetic field increases the free spin number of Cu2+ ions.

关 键 词：SPIN-PEIERLS相变 低温磁化率 锗酸铜 

分 类 号：O482[理学—固体物理]