Feb 12, 2019

Creation of novel material Sr3OsO6 with the highest ferromagnetic transition temperature among insulators


- Breaking the world record for the first time in 88 years -

Overview of the press release

Researchers of Nippon Telegraph and Telephone Corporation (NTT) have synthesized Sr3OsO6, a novel material that exhibits ferromagnetism above 780°C, which is the highest temperature among insulators. In collaboration with the Tsuneyuki Research Group at the University of Tokyo (UTokyo), they have also revealed the electronic state of this material, which is the key to comprehending the origin of the emergent ferromagnetism.

Our discovery surpasses the long-standing Curie temperature (TC) record among insulators for the first time in 88 years and is thus epoch-making for the development of magnetic materials. It also provides fundamental knowledge about the mechanism of the emergent ferromagnetism at high temperatures. Unlike most conventional magnetic materials, our brand-new material is free from Fe (iron) and Co (cobalt) and hence paves a new way to the exploration and development of other novel magnetic materials. Furthermore, the Sr3OsO6 was synthesized in the form of single-crystalline thin films. This suggests that the Sr3OsO6 films can be readily implemented in device fabrication and are thus promising for high-performance magnetic devices that can be stably operated at high temperatures (room temperature to 250°C). Examples of such devices include magnetic random access memories (MRAM) and magnetic sensors.

The research was published in Nature Communications on February 12, 2019.


Fig. 1a: Schematic diagram of Sr3OsO6 (double perovskite). The yellow, red, and blue spheres indicate Sr, Os, and O atoms, respectively. Fig. 1b: Atomic scale microscopy (scanning transmission electron microscopy) image of a Sr3OsO6 film viewed along the [110] direction. We can clearly see the atomic ordering depicted in Fig. 1a.


To read the full press release, please visit the NTT website.


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