论文标题
磁性超导体EUFE $ _ {2} $中的复杂Vortex-Antivortex动力学（AS $ _ {0.7} $ P $ _ {0.3} $）$ _ {2} $
Complex vortex-antivortex dynamics in the magnetic superconductor EuFe$_{2}$(As$_{0.7}$P$_{0.3}$)$_{2}$
论文作者
论文摘要
我们报告了磁性超导体EUFE $ _ {2} $的调查（AS $ _ {0.7} $ P $ _ {0.3} $）$ _ {2} $基于MUON-SPIN光谱光谱和AC磁敏感性（$χ$）的测量值。内部场对温度的依赖性表明EU $^{2+} $磁矩的铁磁有序，并且只有常规的木散射才能在低温下控制纵向弛豫率。同时，我们通过标准的AC敏感性和基于微波炉Coplanar Waveguide谐振器的新技术观察到了易感性$χ^{\ prime \ prime} $的假想成分的丰富现象学。特别是，我们在跨越十个数量级的频率上检测到$χ^{\ prime \ prime} $的几个功能的激活趋势。我们根据受磁体域的基础结构影响的涡流和抗生效的复杂动力学来解释我们的结果。
We report on the investigation of the magnetic superconductor EuFe$_{2}$(As$_{0.7}$P$_{0.3}$)$_{2}$ based on muon-spin spectroscopy and ac magnetic susceptibility ($χ$) measurements. The dependence of the internal field at the muon site on temperature is indicative of a ferromagnetic ordering of Eu$^{2+}$ magnetic moments and only the conventional magnon scattering governs the longitudinal relaxation rate at low temperatures. At the same time, we observe a rich phenomenology for the imaginary component of the susceptibility $χ^{\prime\prime}$ by means of both standard ac susceptibility and a novel technique based on a microwave coplanar waveguide resonator. In particular, we detect activated trends for several features in $χ^{\prime\prime}$ over frequencies spanning ten orders of magnitude. We interpret our results in terms of the complex dynamics of vortices and antivortices influenced by the underlying structure of magnetic domains.
