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arXiv · 1311.2265

Electronic Structure of Magnetic Semiconductor CdCr_2Te_4: A Possible Spin-Dependent Symmetry Filter

Hunter Sims·Karthik Ramasamy·William H. Butler·Arunava Gupta
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Abstract

We present a theoretical investigation of the electronic and magnetic structure of spinel CdCr_2Te_4 using density functional theory, its extensions via onsite Hubbard U interactions, and a screened-hybrid-functional exchange potential. We find that the ground state is semiconducting within the latter approach, and within this magnetic-semiconducting system we compute the complex band structure, finding a slowly decaying evanescent $\tilde{\Delta}_1$ state possibly suitable for realizing a spin-dependent symmetry filter effect.

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Hunter Sims, Karthik Ramasamy, William H. Butler, Arunava Gupta. 2013-11-10. Electronic Structure of Magnetic Semiconductor CdCr_2Te_4: A Possible Spin-Dependent Symmetry Filter. https://doi.org/10.1063/1.4827818

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