论文标题
磁场诱导的WO2的磁场诱导的绝缘子 - 金属转变在500 t时
Magnetic-field-induced insulator-metal transition in W-doped VO2 at 500 T
论文作者
论文摘要
在相关电子系统中，金属 - 绝缘体（MI）过渡长期以来一直是材料科学中的核心且有争议的问题。二氧化钒（VO2）在340 K处表现出一阶MI过渡。在半个多世纪以来，人们一直在争论电子相关性还是由于二聚体Vions引起的结构不稳定性是这种MI过渡背后的更重要的驱动力。在这里，我们表明500吨的超高磁场呈现出钨（W）掺杂的VO2金属的绝缘体相。自旋zeeman对V离子D电子的效应在绝缘阶段解离二聚体，从而导致电子的定位。由于Mott-Hubbard的差距本质上不取决于自旋的自由度，因此结构不稳定可能是MI过渡背后的更重要的驱动力。
Metal-insulator (MI) transitions in correlated electron systems have long been a central and controversial issue in material science. Vanadium dioxide (VO2) exhibits a first-order MI transition at 340 K. For more than half a century, it has been debated whether electronic correlation or the structural instability due to dimerised V ions is the more essential driving force behind this MI transition. Here, we show that an ultrahigh magnetic field of 500 T renders the insulator phase of tungsten (W)-doped VO2 metallic. The spin Zeeman effect on the d electrons of the V ions dissociates the dimers in the insulating phase, resulting in the delocalisation of electrons. Because the Mott-Hubbard gap essentially does not depend on the spin degree of freedom, the structural instability is likely to be the more essential driving force behind the MI transition.
