论文标题
局部温度在CA2RUO4的电流驱动金属绝缘体过渡中的作用
Role of local temperature in the current-driven metal-insulator transition of Ca2RuO4
论文作者
论文摘要
最近据报道，连续电流是触发CA2RUO4中电子结构和金属构造器转变（MIT）变化的强大控制参数。然而，尚未阐明麻省理工学院的空间演化以及不可避免的焦耳加热的含义，这通常是由于难以评估局部样品温度的困难而阻碍。在这项工作中，我们在通过电流控制MIT时对单晶CA2RUO4进行红外热成像。相变的发射率的变化使我们能够在增加电流时监测金属相的逐渐形成和扩展。我们的局部温度测量表明，在我们的实验分辨率中，MIT始终发生在相同的局部过渡温度下，如果由温度或电流驱动，则无关紧要。我们的结果强调了在研究电流流动下强烈相关的材料时，局部加热，相共存和微观不均匀性的重要性。
It was recently reported that a continuous electric current is a powerful control parameter to trigger changes in the electronic structure and metal-insulator transitions (MITs) in Ca2RuO4. However, the spatial evolution of the MIT and the implications of the unavoidable Joule heating have not been clarified yet, often hindered by the difficulty to asses the local sample temperature. In this work, we perform infrared thermal imaging on single-crystal Ca2RuO4 while controlling the MIT by electric current. The change in emissivity at the phase transition allows us to monitor the gradual formation and expansion of metallic phase upon increasing current. Our local temperature measurements indicate that, within our experimental resolution, the MIT always occurs at the same local transition temperatures, irrespectively if driven by temperature or by current. Our results highlight the importance of local heating, phase coexistence, and microscale inhomogeneity when studying strongly correlated materials under the flow of electric current.
