Spin-Triplet Pairing Induced by Hund's Rule Exchange in Orbitally Degenerate Systems: Hartree-Fock Approximation

• Authors: M. Zegrodnik , J. Spałek
• Languages of publication: EN

Abstracts

EN

We discuss the spin-triplet pairing mechanism induced by the Hund rule ferromagnetic exchange. We include explicitly the effect of interband hybridization and treat the problem by starting from an extended Hubbard model for a doubly degenerate band, making the simplest Hartree-Fock approximation for the part involving the pairing and the Hubbard interaction. The conditions of stability of various phases are determined as a function of both band filling and microscopic parameters. The phase diagram contains regions of stability of the spin-triplet superconducting phase coexisting with either saturated or non-saturated ferromagnetism. Phase diagrams for the cases of constant density of states and that of square lattice have been provided. The influence of hybridization on the stability of considered phases, as well as the temperature dependences of magnetic moment and the superconducting gap are also discussed.

Keywords

EN

74.20.-z; 74.25.Dw; 75.10.Lp

Discipline

• 74.20.-z: Theories and models of superconducting state
• 75.10.Lp: Band and itinerant models
• 74.25.Dw: Superconductivity phase diagrams

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2012
• Volume: 121
• Issue: 5-6
• Pages: 1051-1055

Dates

published

2012-05

Contributors

author

M. Zegrodnik

• AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, al. A. Mickiewicza 30, 30-059 Krakow, Poland

author

J. Spałek

• AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, al. A. Mickiewicza 30, 30-059 Krakow, Poland
• Marian Smoluchowski Institute of Physics, Jagiellonian University, W.S. Reymonta 4, 30-059 Kraków, Poland

References

• 1. Y. Maeno, H. Hashimoto, K. Yoshida, S. Nishizaki, T. Fujita, J.G. Bednorz, Nature 372, 532 (1994)
• 2. S.S. Saxena, P. Agarwal, K. Ahilan, F. M. Grosche, R.K.W. Haselwimmer, M.J. Steiner, E. Pugh, I. R. Walker, S.R. Julian, P. Monthoux, G.G. Lonzarich, A. Huxley, I. Sheikin, D. Braithwaite, J. Flouquet, Nature 406, 587 (2000)
• 3. N. Tateiwa, T.C. Kobayashi, K. Hanazono, K. Amaya, Y. Haga, R. Settai, Y. Onuki, J. Phys., Condens. Matter 13, 117 (2001)
• 4. For additional introduction see: J. Spałek, Acta Phys. Pol. A 111, 409 (2007)
• 5. K. Klejnberg, J. Spałek, J. Phys., Condens. Matter 11, 6553 (1999)
• 6. J. Spałek, Phys. Rev. B 63, 104513 (2001)
• 7. K. Klejnberg, J. Spałek, Phys. Rev. B 61, 15542 (2000)
• 8. T. Nomura, K. Yamada, J. Phys. Soc. Jpn. 71, 1993 (2002)
• 9. J. Spałek, P. Wróbel, W. Wójcik, Physica C 387, 1 (2003)
• 10. P. Wróbel, Ph.D. Thesis, Jagiellonian University, Kraków 2004, unpublished
• 11. Shun-Qing Shen, Phys. Rev. B 57, 6474 (1998)
• 12. J. Dukelsky, C. Esebagg, S. Pittel, Phys. Rev. Lett. 88, 062501 (2002)
• 13. S. Inagaki, R. Kubo, Int. J. Magn. 4, 139 (1973)

Identifiers

DOI

10.12693/APhysPolA.121.1051