摘要The Fermi surfaces (FS) of LaOFeAs (in kz=0 plane) consist of two hole-type circles around Γ point, which do not touch each other, and two electron-type co-centred ellipses around the M point, which are degenerate along the M-X line. By first-principles calculations, here we show that additional degeneracy exists for the two electron-type FS, and the crucial role of F-doping and pressure is to enhance this orbital degeneracy. It is therefore suggested that the inter-orbital fluctuation is important to understand the unconventional superconductivity in these materials.
Abstract：The Fermi surfaces (FS) of LaOFeAs (in kz=0 plane) consist of two hole-type circles around Γ point, which do not touch each other, and two electron-type co-centred ellipses around the M point, which are degenerate along the M-X line. By first-principles calculations, here we show that additional degeneracy exists for the two electron-type FS, and the crucial role of F-doping and pressure is to enhance this orbital degeneracy. It is therefore suggested that the inter-orbital fluctuation is important to understand the unconventional superconductivity in these materials.
(Electron density of states and band structure of crystalline solids)
引用本文:
ZHANG Hai-Jun;XU Gang;DAI Xi;FANG Zhong. Enhanced Orbital Degeneracy in Momentum Space for LaOFeAs[J]. 中国物理快报, 2009, 26(1): 17401-017401.
ZHANG Hai-Jun, XU Gang, DAI Xi, FANG Zhong. Enhanced Orbital Degeneracy in Momentum Space for LaOFeAs. Chin. Phys. Lett., 2009, 26(1): 17401-017401.
[1] Kamihara Y, Watanabe T, Hirano M and Hosono H 2008 J.Am. Chem. Soc. 130 3296 [2] Chen G F, Li Z, Wu D,Li G, Hu W Z, Dong J, Zheng P, Luo JL and Wang N L 2008 Phys. Rev. Lett. 100 247002 [3] Ren Z A, Yang J, Lu W, Yi W, Che G C, Dong X L, Sun L Land Zhao Z X 2008 Materials Research Innovations 12 1 [4] Chen X H, Wu T, Wu G, Liu R H, Chen H and Fang D F 2008 Nature 453 761 [5] Ren Z A, Lu W, Yang J et al 2008 Chin. Phys. Lett. 25 2215 [6] Yang H, Zhu X, Fang L et al 2008 Supercond. Sci.Technol. 21 105001 Chen G F, Li Z, Li G et al 2008 Phys. Rev. Lett. 101 057007 [7] Shan L, Wang Y, Zhu X et al 2008 Europhys. Lett. 83 57004 Zhu X, Yang H, Fang L et al 2008 Supercond. Sci.Technol. 21 105001 Mu G, Zhu X, Fang L et al 2008 Chin. Phys. Lett. 25 2221 [8] Boeri L, Dolgov O V and Golubov A A 2008 Phys. Rev.Lett. 101 026403 [9] Mazin I I, Singh D J, Johannes M D and Du M H 2008 Phys. Rev. Lett. 101 057003 [10] Kuroki K, Onari S, Arita R et al 2008 Phys. Rev.Lett. 101 087004 [11] Leb\'{egue S 2007 Phys. Rev. B 75 035110 [12] Singh D J and Du M H 2008 Phys. Rev. Lett. 100 237003 [13] Xu G, Ming W, Yao Y, Dai X, Zhang S C and Fang Z 2008 Europhys. Lett. 82 67002 [14] Haule K, Shim J H and Kotliar G 2008 Phys. Rev.Lett. 100 226402 [15] Dong J, Zhang H J, Xu G, Li Z, Li G, Hu W Z, Wu D, Chen GF, Dai X, Luo J L, Fang Z and Wang N L 2008 Europhys. Lett. 83 27006 [16] Watanabe T, Yanagi H, Kamiya T, Kamihara Y, Hiramatsu H,Hirano M and Hosono H 2007 Inorg. Chem. 46 7719 [17] Lu W, Yang J, Dong X L, Ren Z A, Che G C, Zhao Z X 2008 New J. Phys. 10 063026 [18]Dai X, Fang Z, Zhou Y and Zhang F C 2008 Phys. Rev.Lett. 101 057008 [19] Wen H H, Mu G, Fang L, Yang H and Zhu X 2008 Europhys. Lett. 82 17009 [20] Ma F J, LU Z Y and Xiang T 2008 cond-mat/0804.3370
2009, Vol. 26 
