论文标题
相变材料中电阻漂移与光学差距之间的关系
Relation between resistance drift and optical gap in phase change materials
论文作者
论文摘要
相变材料中的光学对比与其结构过渡有关。我们首先认识到弗里德尔振荡夫妇在相反的方向传播并提供额外的库仑能量来连接这两个。随着晶体切换阶段的发展，这种能量会获得时间依赖性，而Landau-Zener机制运行，转向种群从价转移到传导带，反之亦然。光谱法表明振荡器能量主导了光学特性，涉及晶体场和自旋轨道相互作用的计算得出了两个结构相的良好估计。进一步的分析将光学间隙与晶体场能以及电导传导的活化能有关。最后的特性表征了无定形相，从而提供了结晶场与激活能之间的联系，并最终与电阻漂移指数。提供光学手段来量化PCM中的电阻漂移可能需要规避制造昂贵的设备和执行耗时尺寸的需求。
The optical contrast in a phase change material is concomitant with its structural transition. We connect these two by first recognizing that Friedel oscillations couple electrons propagating in opposite directions and supply an additional Coulomb energy. As the crystal switches phase, this energy acquires time dependence and the Landau-Zener mechanism operates, steering population transfer from the valence to the conduction band and vice versa. Spectroscopy suggests that the oscillator energy dominates the optical properties and a calculation involving the crystalline field and spin-orbit interaction yields good estimates for of both structural phases. Further analysis relates the optical gap with the crystalline-field energy as well as activation energy for electrical conduction. This last property characterizes the amorphous phase, thereby furnishing a link between the crystalline field and the activation energy and ultimately with the resistance drift exponent. Providing optical means to quantify resistance drift in PCMs could circumvent the need for fabricating expensive devices and performing time consuming measurements.
