U.S.-Czech Republic Materials Research on Novel Magnetic Semiconductors Based on Antimony Telluride [Sb2Te3]

密歇根大学的Ctirad Uher和他的捷克合作伙伴Pardubice大学的Petr Lostak参与了这个美国-捷克材料研究项目，他们将以最近报道的对一类掺入微量钒的碲化锑[Sb2Te3]为基础的各向异性半导体的长程铁磁性观察为基础。他们现在计划研究过渡金属离子在Sb2Te3单晶晶格中的作用，目标是识别出使居里温度提高到超过钒掺杂值(~25K)的掺杂剂。具体地说，研究人员将研究铬、锰、铁、镍和钴的作用。这一合作努力得益于密歇根集团在四氯化钛结构半导体的运输和磁性方面的专业知识，以及捷克合作伙伴在单晶生长和这些材料的表征方面的优势。由于薄膜具有载流子输运和自旋操纵的双重特性，稀磁半导体在这一领域的研究成果可能会在信息技术中得到应用。凝聚态物理方面的这一合作项目通过使美国和中欧的专家能够在彼此感兴趣和能力很强的领域结合互补的人才和共享研究资源，实现了促进科学知识的计划目标。

This U.S.-Czech materials research project involving Ctirad Uher of the University of Michigan and his Czech partner, Petr Lostak at the University of Pardubice, will build upon their recently reported observation of long-range ferromagnetism in a class of ansiotropic semiconductors based on antimony telluride [Sb2Te3], doped with a minute amount of vanadium. They now plan to study the effect of transition metal ions incorporated in the crystal lattice of Sb2Te3 single crystals with the goal of identifying dopants that enhance the Curie temperature beyond the vanadium-doped value (~25K). Specifically, the researchers will examine the role of chromium, manganese, iron, nickel and cobalt. The collaborative effort benefits from the Michigan group's expertise in transport and magnetic properties of tetradymite-type structure semiconductors and the Czech partners' strengths in growth of single crystals and characterization of these materials. Results in this area of diluted magnetic semiconductors may lead to applications in information technology given the promising dual features of charge carrier transport and spin manipulation in thin films. This collaborative project in condensed matter physics fulfills the program objective of advancing scientific knowledge by enabling experts in the United States and Central Europe to combine complementary talents and share research resources in areas of strong mutual interest and competence.