Pd $_{1-x}$ Ni $_x$ /Si界面混合重离子与物质快速相互作用的热峰模型
Assessing thermal spike model of swift heavy ion-matter interaction via Pd$_{1-x}$Ni$_x$/Si interface mixing
摘要：
热锋模型是目前被广泛接受的快重离子与物质相互作用机制。它提供了解释各种SHI诱导的效果，包括跨界面混合。该模型包括电子-声子（e-p）耦合预测晶格温度随时间的演变。SHI混合被认为是瞬态熔融状态下扩散的结果。在这项工作中，我们评估这一概念主要是通过调整电子-p耦合强度采取一系列的Pd $_{1-x}$ Ni $_x$的完全固溶的二元，然后观察100 MeV的Au离子诱导混合整个Pd $_{1-x}$ Ni $_x$ /Si接口。混合的程度已被参数化的辐照引起的变化$Δσ^2$的Pd和Ni的深度分布的方差来自X-射线光电子能谱学。$Δσ^2$的$x$依赖性遵循一条向上凹且具有显著最小值的曲线。从理论上讲，用密度泛函理论确定的e-p耦合强度已被用于求解适合于TSM的方程，然后计算出与$Δσ^2$成比例的等效量L $^2$。然而，L $^2$随$x$单调增加，没有任何最小值，从而在实验和理论之间产生令人信服的差异。可能有比TSM和瞬时熔融态扩散更重要的机制在起作用，这在此时是无法预见的。
英文摘要：
Thermal spike model (TSM) is presently a widely accepted mechanism of swift heavy ion (SHI) - matter interaction. It provides explanation to various SHI induced effects including mixing across interfaces. The model involves electron-phonon (e-p) coupling to predict the evolution of lattice temperature with time. SHI mixing is considered to be a result of diffusion in transient molten state thus achieved. In this work, we assess this conception primarily via tuning the e-p coupling strength by taking a series Pd$_{1-x}$Ni$_x$ of a completely solid soluble binary, and then observing 100 MeV Au ion induced mixing across Pd$_{1-x}$Ni$_x$/Si interfaces. The extent of mixing has been parametrised by the irradiation induced change $Δσ^2$ in variances of Pd and Ni depth profiles derived from X-ray photoelectron spectroscopy. The $x$-dependence of $Δσ^2$ follows a curve that is concave upward with a prominent minimum. Theoretically, e-p coupling strength determined using density functional theory has been used to solve the equations appropriate to TSM, and then an equivalent quantity L$^2$ proportional to $Δσ^2$ has been calculated. L$^2$, however, increases monotonically with $x$ without any minimum, bringing out a convincing disparity between experiment and theory. Perhaps some mechanisms more than the TSM plus the transient molten state diffusion are operative, which can not be foreseen at this point of time.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
