Nat Mater. 2011 Oct 2;10(11):853-6. doi: 10.1038/nmat3130.
Electrical control of magnetic properties is crucial for device applications in the field of spintronics. Although the magnetic coercivity or anisotropy has been successfully controlled electrically in metals as well as in semiconductors, the electrical control of Curie temperature has been realized only in semiconductors at low temperature. Here, we demonstrate the room-temperature electrical control of the ferromagnetic phase transition in cobalt, one of the most representative transition-metal ferromagnets. Solid-state field effect devices consisting of a ultrathin cobalt film covered by a dielectric layer and a gate electrode were fabricated. We prove that the Curie temperature of cobalt can be changed by up to 12 K by applying a gate electric field of about ±2 MV cm(-1). The two-dimensionality of the cobalt film may be relevant to our observations. The demonstrated electric field effect in the ferromagnetic metal at room temperature is a significant step towards realizing future low-power magnetic applications.
电控制磁性在自旋电子学领域的器件应用中至关重要。虽然在金属和半导体中已经成功地实现了磁矫顽力或各向异性的电控制，但在低温下仅在半导体中实现了居里温度的电控制。在这里，我们证明了室温下钴的铁磁相变的电控制，钴是最具代表性的过渡金属铁磁体之一。制备了由覆盖有介电层和栅电极的超薄钴膜组成的固态场效应器件。我们证明，通过施加约±2 MV cm(-1)的栅电场，钴的居里温度可以改变高达 12 K。钴膜的二维性可能与我们的观察结果有关。在室温下铁磁金属中表现出的电场效应是朝着实现未来低功耗磁应用迈出的重要一步。
