论文标题
磁性掺杂bi $ _ {0.97-x} $ SB $ _ {0.03} $单晶
Magneto-transport and Berry phase in magnetically doped Bi$_{0.97-x}$Sb$_{0.03}$ single crystals
论文作者
论文摘要
我们报告了磁性（M = Ni和Fe）的单晶中的大磁磁性（MR）和Shubnikov-De Haas（SDH）振荡，掺杂m $ _x $ _x $ _x $ _ $ _ {0.97-x} $ _ {0.97-x} $ sb $ _sb $ _ {0.03} $ {0.03} $（$ x = $ x = $ 0，0.02，0.02）拓扑媒体胰岛胰岛素。 R $ \ bar {3} $ M对称性和相位已通过X射线衍射数据的Rietveld改进来确认。有趣的是，在$ x = $ 0的样本中发现了磁场引起的相位从半金属质量到半导体类型的相变。此外，我们在纵向模式下观察到MR在横向模式下高达15个特斯拉的线性行为，而SDH振荡在纵向模式下是相对于电流和晶体平面的。对于父样本，我们通过在横向模式下与修改后的H-L-N方程的MR数据拟合MR数据，发现了连贯的长度L $ _D = $ 12.7 nm。发现使用快速傅立叶变换方法（LLL）扇形图的SDH振荡的提取频率对于父和Ni掺杂样品而言是一致的。与Fermi能量的变化相比，在掺杂的Ni中，确定的费米表面积在Ni中略大。 Kohler的图表示100 K以下的单个散射机制。更重要的是，在LL粉丝图的帮助下，分析揭示了非零的浆果期$ ϕ _ {\ rm B} = - $（1 $ \ pm $ 0.1）$π$，证明了非宗教拓扑状态在dirac the dirac Poiltion in the dirac Points in parted and parents and partent and and and ni doped same and ni doped same and ni doppect and ni doppect and dirac Point same and。
We report large magnetoresistance (MR) and Shubnikov-de Haas (SdH) oscillations in single crystals of magnetically (M= Ni and Fe) doped M$_x$Bi$_{0.97-x}$Sb$_{0.03}$ ($x=$ 0, 0.02) topological insulators. The R$\bar{3}$m symmetry and phase have been confirmed by the Rietveld refinement of x-ray diffraction data. Interestingly, a magnetic field induced phase transition from semi-metallic to semi-conducting type is found with the energy gap around 80 meV at 15 Tesla in the $x=$ 0 sample. Moreover, we observe linear behavior of MR up to 15 Tesla in transverse mode and SdH oscillations in longitudinal mode where the field direction is with respect to the current and crystal plane. For the parent sample, we found the coherence length L$_ϕ=$ 12.7 nm through the fitting of MR data in transverse mode with modified H-L-N equation. The extracted frequencies of SdH oscillations using the fast Fourier transform method and Landau level (LL) fan diagram are found to be consistent for the parent and Ni doped samples. The determined Fermi surface area is found to be slightly larger in Ni doped as compared to the parent sample possibly due to change in the Fermi energy. The Kohler's plot indicates a single scattering mechanism below 100 K. More importantly, the analysis with the help of LL fan diagram reveals the non-zero Berry phase $ϕ_{\rm B}= -$(1$\pm$0.1)$π$, which demonstrates the non-trivial topological states near the Dirac point in the parent and Ni doped samples.
