论文标题
在金属 - 绝缘体过渡中的相位界面处的极性依赖性加热
Polarity dependent heating at the phase interface in metal-insulator transitions
论文作者
论文摘要
在许多情况下，电流驱动的绝缘子 - 金属转变是由焦耳加热驱动的，与所施加电流的平方成比例。 CA $ _2 $ ruo $ _4 $的最新纳米成像实验揭示了一个金属 - 绝缘体相边界，该边界取决于应用电流的方向，这表明重要的非加热效果。在这些结果的驱动下，我们研究了电流在包含金属和绝缘阶段界面的系统中的效果。从一般的宏观onsager传输理论中衍生热平衡方程，揭示了与界面上电流成正比的加热项，以及Seebeck系数的不连续性，因此可以在界面上生成或去除热量，取决于与物质属性的电流方向相对的方向。对于适合CA $ _2 $ ruo $ _4 $的参数，此加热可以与焦耳加热相当或大。证明相关实验几何形状的简化模型可提供与实验一致的结果。讨论了将结果扩展到其他不均匀的金属绝缘体过渡系统。
Current-driven insulator-metal transitions are in many cases driven by Joule heating proportional to the square of the applied current. Recent nano-imaging experiments in Ca$_2$RuO$_4$ reveal a metal-insulator phase boundary that depends on the direction of an applied current, suggesting an important non-heating effect. Motivated by these results, we study the effects of an electric current in a system containing interfaces between metallic and insulating phases. Derivation of a heat balance equation from general macroscopic Onsager transport theory, reveals a heating term proportional to the product of the current across the interface and the discontinuity in the Seebeck coefficient, so that heat can either be generated or removed at an interface, depending on the direction of the current relative to the change in material properties. For parameters appropriate to Ca$_2$RuO$_4$, this heating can be comparable to or larger than Joule heating. A simplified model of the relevant experimental geometry is shown to provide results consistent with the experiments. Extension of the results to other inhomogeneous metal-insulator transition systems is discussed.
