Orientation dependence of swift heavy ion track formation in potassium titanyl phosphate
Orientation dependence of swift heavy ion track formation in potassium titanyl phosphate
复制标题
DOI：
10.1557/jmr.2016.184
复制
发表时间：
2016-08
影响因子：
2.7
通讯作者：
Yujie Ma;Pablo Mota Santiago;Matias Rodriguez;F. Kremer;Daniel Schauries;B. Afra;T. Bierschenk;D. Llewellyn;F. Lu;M. Ridgway;P. Kluth
中科院分区：
文献类型：
--
作者：
Yujie Ma;Pablo Mota Santiago;Matias Rodriguez;F. Kremer;Daniel Schauries;B. Afra;T. Bierschenk;D. Llewellyn;F. Lu;M. Ridgway;P. Kluth
x 切面和 z 切面的磷酸氧钛钾晶体均用 185 MeV Au 离子辐照。使用小角 X 射线散射 (SAXS)、透射电子显微镜 (TEM) 和原子力显微镜 (AFM) 研究所得离子轨迹的形态。 SAXS 测量表明存在圆柱形离子轨迹，其边界陡峭，与周围基质相比密度对比度为 1 ± 0.5%，与非晶轨迹一致。轨迹半径取决于晶体取向，沿 x 轴测量的离子轨迹为 6.0 ± 0.1 nm，沿 z 轴测量的离子轨迹为 6.3 ± 0.1 nm。横截面和平面图中的 TEM 图像显示非晶态离子轨迹，其半径与 SAXS 分析确定的半径相当。 AFM 检测到的覆盖样品表面的突出小丘与离子轨迹内非晶材料的密度低于周围基质的情况一致。使用非弹性热尖峰模型进行的模拟表明，沿 z 轴和 x 轴的热导率差异可以部分解释沿这些方向的不同轨道半径。
Potassium titanyl phosphate crystals in both x-cut and z-cut were irradiated with 185 MeV Au ions. The morphology of the resulting ion tracks was investigated using small angle x-ray scattering (SAXS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). SAXS measurements indicate the presence of cylindrical ion tracks with abrupt boundaries and a density contrast of 1 ± 0.5% compared to the surrounding matrix, consistent with amorphous tracks. The track radius depends on the crystalline orientation, with 6.0 ± 0.1 nm measured for ion tracks along the x -axis and 6.3 ± 0.1 nm for those along the z -axis. TEM images in both cross-section and plan-view show amorphous ion tracks with radii comparable to those determined from SAXS analysis. The protruding hillocks covering the sample surface detected by AFM are consistent with a lower density of the amorphous material within the ion tracks compared to the surrounding matrix. Simulations using an inelastic thermal-spike model indicate that differences in the thermal conductivity along the z — and x -axis can partially explain the different track radii along these directions.