论文标题
分子束外延的结构和磁特性生长的硒化铬薄膜
Structural and Magnetic Properties of Molecular Beam Epitaxy Grown Chromium Selenide Thin Films
论文作者
论文摘要
硒化薄膜是在Al $ {_ 2} $ o $ {_ 3} $（0001）和SI（111） - （7 $ {\ times} $ 7）底物的基质上使用分子束的同一（MBE）。反射高能电子衍射和扫描隧道显微镜中的三角形结构的尖锐条纹表明沿C轴的平滑膜生长，并且与六角形表面非常相似。 X射线衍射模式以17.39Å的C轴晶格常数确认沿C轴的生长。根据温度依赖性电阻率计算，生长的膜是半导体的，其小带隙约为0.034 eV。通过磁交换偏置测量值估计，膜的抗磁性性质约为40 K。在40 K以下观察到较大的平面外交换偏置，以及较小的面内交换偏置。根据不同的模型，分析了交换偏置训练效果，并观察到遵循修改的幂律衰减行为。
Chromium selenide thin films were grown epitaxially on Al${_2}$O${_3}$(0001) and Si(111)-(7${\times}$7) substrates using molecular beam epitaxy (MBE). Sharp streaks in reflection high-energy electron diffraction and triangular structures in scanning tunneling microscopy indicate a flat smooth film growth along the c-axis, and is very similar to that from a hexagonal surface. X-ray diffraction pattern confirms the growth along the c-axis with c-axis lattice constant of 17.39 Å. The grown film is semiconducting, having a small band gap of about 0.034 eV, as calculated from the temperature dependent resistivity. Antiferromagnetic nature of the film with a Néel temperature of about 40 K is estimated from the magnetic exchange bias measurements. A larger out-of-plane exchange bias, along with a smaller in-plane exchange bias is observed below 40 K. Exchange bias training effects are analyzed based on different models and are observed to be following a modified power-law decay behavior.
