The Magnetic Properties of 1111-type Diluted Magnetic Semiconductor (La1−xBax)(Zn1−xMnx)AsO in the Low Doping Regime

Condensed Matter

Zhang, Haojie¹  Wang, Kai²  Zhi, Guoxiang³ 

[1] Author to whom correspondence should be addressed;Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China;Department of Physics, Zhejiang University, Hangzhou 310027, China

关键词: ferromagnetic ordering;    antiferromagnetic exchange interaction;    ferromagnetic coupling;    carrier-mediated;   

DOI  :  10.3390/condmat3040042

学科分类：凝聚态物理

来源: mdpi

【 摘 要 】

We investigated the magnetic properties of (La1 − x Ba x)(Zn1 − x Mn x)AsO with x varying from 0.005 to 0.05 at an external magnetic field of 1000 Oe. For doping levels of x ≤ 0.01, the system remains paramagnetic down to the lowest measurable temperature of 2 K. Only when the doping level increases to x = 0.02 does the ferromagnetic ordering appear. Our analysis indicates that antiferromagnetic exchange interactions dominate for x ≤ 0.01, as shown by the negative Weiss temperature fitted from the magnetization data. The Weiss temperature becomes positive, i.e., ferromagnetic coupling starts to dominate, for x ≥ 0.02. The Mn-Mn spin interaction parameter ∣ 2 J /k B∣ is estimated to be in the order of 10 K for both x ≤ 0.01 (antiferromagnetic ordered state) and x ≥ 0.02 (ferromagnetic ordered state). Our results unequivocally demonstrate the competition between ferromagnetic and antiferromagnetic exchange interactions in carrier-mediated ferromagnetic systems.

【 授权许可】

CC BY