Electronic Structure of Transition-Metal Based Cu2GeTe3 Phase Change Material: Revealing the Key Role of Cu d Electrons
Electronic Structure of Transition-Metal Based Cu2GeTe3 Phase Change Material: Revealing the Key Role of Cu d Electrons
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DOI：
10.1021/acs.chemmater.7b02436
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发表时间：
2017-08
影响因子：
8.6
通讯作者：
Y. Saito;Y. Sutou;P. Fons;S. Shindo;X. Kozina;J. Skelton;A. Kolobov;Keisuke L. I. Kobayashi
中科院分区：
文献类型：
--
作者：
Y. Saito;Y. Sutou;P. Fons;S. Shindo;X. Kozina;J. Skelton;A. Kolobov;Keisuke L. I. Kobayashi
使用硬X射线光电子能谱和密度泛函理论模拟系统地研究了过渡金属基Cu2GeTe3相变材料的沉积态非晶相和晶相的电子结构。我们揭示了 Cu d 电子，并揭示了 d 电子在成键中的参与在相变过程中发挥着重要作用。即使在不具有共振键合的四面体键合晶体结构中，也能保持大的电对比度和快速切换。根据所获得的结果，我们提出以前被忽视的基于过渡金属的相变材料不仅将成为非易失性存储器应用的候选材料，而且也将成为新兴应用的候选材料。
The electronic structure of the as-deposited amorphous and crystalline phases of the transition-metal based Cu2GeTe3 phase-change material has been systematically investigated using hard-X-ray photoemission spectroscopy and density-functional theory simulations. We shed light on Cu d electrons and reveal that participation of d electrons in the bonding plays an important role during the phase-change process. A large electrical contrast as well as fast switching is preserved even in the tetrahedrally-bonded crystal structure, which does not possess resonant bonding. Based on the obtained results, we propose that transition-metal based phase change materials that have been previously overlooked will be candidates not only for non-volatile memory applications, but also for emerging applications.