Тип публикации: статья из журнала
Год издания: 2015
Идентификатор DOI: 10.1134/S0021364015180162
Аннотация: In the framework of the t-J (1)-J (2)-V model, the integral equation determining the order parameter Delta(p) of the superconducting phase is derived for an ensemble of strongly correlated fermions on a triangular lattice using the diagram technique for the Hubbard operators. Taking into account the interaction between the Hubbard Показать полностьюfermions within two coordination spheres, we demonstrate that the exact analytical solution Delta 2(p) of this equation for the superconducting phase with the () symmetry can be expressed as a superposition of two chiral basis functions. This gives rise to a new set of nodal points for the complex parameter Delta 2(p). Moreover, at some critical value x (c) of the charge carrier density, we obtain a gapless phase with six Dirac points. The passing of x through x = x (c) is accompanied by the topological quantum transition corresponding to the change in the topological parameter Q.
Журнал: JETP LETTERS
Выпуск журнала: Vol. 102, Is. 6
Номера страниц: 361-366
ISSN журнала: 00213640
Место издания: NEW YORK
Издатель: MAIK NAUKA/INTERPERIODICA/SPRINGER