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arXiv · 2408.08680

Growth of Ba_2CoWO_6 Single Crystals and their Magnetic, Thermodynamic and Electronic Properties

Abanoub R. N. Hanna·A. T. M. N. Islam·C. Ritter·S. Luther·R. Feyerherm·B. Lake
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Abstract

This study explores the bulk crystal growth, structural characterization, and physical property measurements of the cubic double perovskite Ba_2CoWO_6(BCWO). In BCWO, Co+2 ions form a face-centered cubic (FCC) lattice with non-distorted cobalt octahedra. The compound exhibits long-range antiferromagnetic order below TN = 14 K. Magnetization data indicated a slight anisotropy along with a spin-flop transition at 10 kOe , a saturation field of 310 kOe and an ordered moment of 2.17 Mu_B at T = 1.6 K. Heat capacity measurements indicate an effective j = 1/2 ground state configuration, resulting from the combined effects of the crystal electric field and spin-orbit interaction. Surface photovoltage analysis reveals two optical gaps in the UV-Visible region, suggesting potential applications in photocatalysis and photovoltaics. The magnetic and optical properties highlight the significant role of orbital contributions within BCWO, indicating various other potential applications.

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Abanoub R. N. Hanna, A. T. M. N. Islam, C. Ritter, S. Luther, R. Feyerherm, B. Lake. 2024-08-16. Growth of Ba_2CoWO_6 Single Crystals and their Magnetic, Thermodynamic and Electronic Properties. https://arxiv.org/abs/2408.08680

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