Тип публикации: статья из журнала (материалы конференций, опубликованные в журналах)
Конференция: International Conference on Magnetism (ICM 2006); Kyoto, JAPAN; Kyoto, JAPAN
Год издания: 2007
Идентификатор DOI: 10.1016/j.jmmm.2006.10.065
Ключевые слова: superconductivity; t-J-model
Аннотация: The diagram technique method for Hubbard operators has been used to describe the superconducting (SC) phase of the t-t '-t ''-J* model. The new exact representation for the matrix one-particle Green's function has been derived. The main peculiarity of the obtained representation lies in the fact that not only anomalous components oПоказать полностьюf the mass operator Sigma(0 sigma),(sigma) over bar (0) (k, i omega(m)) but also an anomalous components P-0 sigma,P-(sigma) over bar (0)(k, i omega(m)) of the matrix strength operators P(k, i omega(m)) are taken into account. In the one-loop approximation all analytical contributions of the normal Sigma(0 sigma,0 sigma)(k; i omega(m)), P-0 sigma,P-0 sigma (k, i omega(m)) and of the anomalous Sigma(0 sigma),(sigma) over bar sigma(k, i omega(m)), P-0 sigma,(sigma) over bar0(k, i omega(m)) components mass and strength operators have been calculated. The Matsubara's frequencies dependence of the anomalous strength operator gave rise to description of the SC-phase by an infinite system of integral equations. Taking into account hoppings of electrons between sites situated within the limits of three coordination spheres this system was solved exactly. The in. uence of three-site interactions and intensity of hoppings on the existence of SC-phase with d(x2)-(y2)-type of the order parameter symmetry have been analyzed. It has been analyzed also the in. uence of the normal component P0 sigma,0 sigma(k, i omega(m)) on the function distribution of the Fermi- quasiparticles in the normal phase. It is shown that strong electron correlations give rise to degradation of the Fermi function even if the temperature much less than Fermi energy. (c) 2006 Elsevier B.V. All rights reserved.
Журнал: JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
Выпуск журнала: Vol. 310, Is. 2, Part1
Номера страниц: 104-106
ISSN журнала: 03048853
Место издания: AMSTERDAM
Издатель: ELSEVIER SCIENCE BV