tailieunhanh - Báo cáo hóa học: " Electronic and magnetic properties of SnO2/CrO2 thin superlattices"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Electronic and magnetic properties of SnO2/CrO2 thin superlattices | Borges et al. Nanoscale Research Letters 2011 6 146 http content 6 1 146 o Nanoscale Research Letters a SpringerOpen Journal NANO REVIEW Open Access Electronic and magnetic properties of SnO2 CrO2 thin superlattices 1 2 3 4 1 Pablo D Borges Luisa MR Scolfaro Horácio W Leite Alves Eronides F da Silva Jr Lucy VC Assali Abstract In this article using first-principles electronic structure calculations within the spin density functional theory alternated magnetic and non-magnetic layers of rutile-CrO2 and rutile-SnO2 respectively in a CrO2 n SnO2 n superlattice SL configuration with n being the number of monolayers which are considered equal to 1 2 . 10 are studied. A half-metallic behavior is observed for the CrO2 n SnO2 n SLs for all values of n. The ground state is found to be FM with a magnetic moment of 2 gB per chromium atom and this result does not depend on the number of monolayers n. As the FM rutile-CrO2 is unstable at ambient temperature and known to be stabilized when on top of SnO2 the authors suggest that CrO2 n SnO2 n SLs may be applied to spintronic technologies since they provide efficient spin-polarized carriers. Introduction A variety of heterostructures have been studied for spintronics applications and they have proved to have a great potential for high-performance spin-based electronics 1 . A key requirement in developing most devices based on spins is that the host material must be ferromagnetic FM above 300 K. In addition it is necessary to have efficient spin-polarized carriers. One approach to achieve the spin injection is to create built-up superlattices SLs of alternating magnetic and non-magnetic materials. One attempt has already been made by Zaoui et al. 2 through ab initio electronic structure calculations for the one monolayer ZnO 1 CuO 1 SL with the aim of obtaining a half-metallic behavior material since they are 100 spin polarized at the Fermi level and therefore appear ideal for a well-defined carrier spin .