Ferrimagnetic and spin-glass transition in the Aurivillius compound SrBi5Ti4Cr0.5Co0.5O18
Ferrimagnetic and spin-glass transition in the Aurivillius compound SrBi5Ti4Cr0.5Co0.5O18
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DOI：
10.1063/1.4922869
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发表时间：
2015-06
影响因子：
3.2
通讯作者：
B. Yuan;Jie Yang;X. Zuo;D. Song;Xianwu Tang;Xuebin Zhu;J. Dai;W. Song;Yuping Sun
中科院分区：
文献类型：
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作者：
B. Yuan;Jie Yang;X. Zuo;D. Song;Xianwu Tang;Xuebin Zhu;J. Dai;W. Song;Yuping Sun
采用改进的Pechini法合成了单相多晶SrBi5Ti4CrO18和SrBi5Ti4Cr0.5Co0.5O18。这两个样品都具有空间群为B2cb的正交结构。根据X射线光电子能谱的结果，认为铬的价态为+3，钴离子以Co2+和Co3+的形式存在。样品SrBi5Ti4CrO18表现为顺磁状态，而SrBi5Ti4Cr0.5Co0.5O18样品在89K时由于Cr基和Co基亚晶格的反铁磁耦合而经历亚铁磁性相变。此外，交流磁化率和磁弛豫测量结果表明，在89K以下，SrBi5Ti4Cr0.5Co0.5O18表现出典型的自旋玻璃行为，zν=6.02，τ0=(1.75±0.33)×10−14 S。其中，SrBi5Ti4Cr0.5Co0.5O18的介电常数和介电损耗在89K附近均表现出介电弛豫特性，其介电激活能为(0.14±0.02)eV。
Single-phase polycrystalline SrBi5Ti4CrO18 and SrBi5Ti4Cr0.5Co0.5O18 were synthesized by a modified Pechini method. Both samples have an orthorhombic structure with the space group B2cb. The valence state of Cr is suggested to be +3 and the Co ions exist in the form of Co2+ and Co3+ based on the results of x-ray photoelectron spectroscopy. The sample SrBi5Ti4CrO18 exhibits the paramagnetic state, whereas SrBi5Ti4Cr0.5Co0.5O18 undergoes a ferrimagnetic transition at 89 K originating from the antiferromagnetic coupling of Cr-based and Co-based sublattices. In addition, SrBi5Ti4Cr0.5Co0.5O18 shows a typical spin-glass behavior below 89 K with zν = 6.02 and τ0 = (1.75 ± 0.33) × 10−14 s as evidenced by the results of the frequency dependence of ac susceptibility and magnetic relaxation measurements. In particular, both the dielectric constant and dielectric loss of SrBi5Ti4Cr0.5Co0.5O18 exhibit the characteristics of dielectric relaxation around 89 K with the activation energy of (0.14 ± 0.02) eV, which can be...