First-Principle Study on Half-Metallic Ferromagnetism and Structural Stability of C-Doped Alkaline-Earth Chalcogenides under Pressure

Abstract:

Three half-metallic ferromagnets with NaCl structure, X₄CS₃ (X = Mg, Ca and Sr) are investigated by the first principle calculations based on the density functional theory in thegeneralized gradient approximation. Non-spin and spin polarized calculations are done to obtain the lattice constants, the equilibrium cell volumes, the stable energies and the magnetic moments of X₄CS₃, and band structure and density of states for X₄CS₃ at high pressure are calculated. From the calculations it has been found that X₄CS₃ is stable in the FM state. The corresponding lattice constants and the equilibrium cell volumes in FM are greater than that in NM. The magnetic moment of X₄CS₃ decrease as pressure increases, and a second order magnetic phase transition of Sr₄CS₃ from FM to NM state at pressure of 140GPa, but a second order magnetic phase transitions of Mg₄CS₃ and Ca₄CS₃ have not been found. According to the band and the density of states, as the pressure increases the half-metallic nature of X₄CS₃ destroyed.

• Periodical: Advanced Materials Research (Volume 1052)
• Pages: 155-162
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1052.155
• Online since: October 2014
• Authors: Hui Zhao, Qian Han
• Keywords: Density Functional Theory, Ferromagnetic, Half-Metallic, Pressure

References

[1] Wolf S A, Awschalom D D, Buhrman R A. Science, 2001, 294: 1488.

[2] Groot R A, Mueller F M, van Engen P G, Buschow K H J. Phys. Rev. Lett., 1983, 50: (2024).

[3] Kobayashi K, Kimura T, Sawada H, Terakura K, Tokura Y. Nature(London), 1998, 395: 677.

[4] Leuken H V, de Groot R A. Phys. Rev. Lett. 1995, 74: 1171.

[5] Liu B G. Phys. Rev. B, 2003, 67: 172411.

[6] Cai J W, Prog. Phys. 2006, 26: 180.

[7] Ren S K, Zhang F M, Du Y W. Prog. Phys. 2004, 24: 381.

[8] Xie W H, Liu B G. J. Appl. Phys. 2004, 96: 3559.

[9] Asano Y, Tanaka Y, Golubov A. A. Phys. Rev. Lett. 2007, 98: 107002.

[10] Wan X G, Kohno M, Hu X. Phys. Rev. Lett. 2005, 95: 146602.

[11] Xie W H, Liu B G, Pettifor D G. Phys. Rev. B., 2003, 68: 134407.

[12] Lauer M, Valenti R, Kandpal H C, Seshadri R. Phys. Rev. B., 2004, 69: 075117.

[13] Kahal L, Zaoui A, Ferhat M. J. Appl. Phys. 2007, 101: 093912.

[14] Srivastava V, Rajagopalan M, Sanyal S P. Eur. Phys. J. B, 2008, 61: 131-139.

[15] Liu X B, Altounian Z. J. Appl. Phys., 2007, 101: 09G511.

[16] Srivastava V, Sanyal S P, Pajagopalan M. Indian Journal of Pure & Applied Physics, 2008, 46: 397-399.

[17] Gokoglu G, Gulseren O. Eur. Phys. J. B, 2010, 76: 321-326.

[18] Liu J, Chen L, Dong H N, Zheng R L. Appl. Phys. Lett., 2009, 95: 132502.

[19] Droghettia A, Sanvito S. Appl. Phys. Lett., 2009, 94: 252505.

[20] Segall M D, Lindan P J D, Probert M J, J. Phys. Condens. Matter, 2002, 14: 2717.

[21] Milman V, Winkler B, White J A. Int. J. Quantum. Chem., 2000, 77: 895-910.

[22] Perdew P J, Burke K, Ernzerhof M. Phys. Rev. Lett., 1996, 77: 3865-3868.