On the theory of layered high-temperature superconductors

Antiferromagnetism and superconductivity in a model with extended pairing interactions

“…In exactly similar manner ∆ t2 gets dynamically generated when both AF and d xy SC order parameters (i.e., b 0 and ∆ 2 ) appear simultaneously while the pairing interaction(W 2 ) is zero in eqn. (10). Simultaneous presence of AF and singlet d + id SC state dynamically generates the triplet d + id SC state.…”

“…Extensive literature exists for models in the opposite limit of repulsive extended range interactions where the classical limit gives rise to charge density waves [23]. In the absence of V 2 , Monte-Carlo calculations [10] of model (1) shows AF phase at all densities. At half-filling the ground state is Néel ordered while away from half-filling there is evidence for phase separation between AF ordered and empty domains.…”

“…with W 1,2 set to zero in equations (6)- (10). In order to obtain the phase diagram in the temperaturedensity plane, the particle density n is calculated from n = − ∂F ∂µ…”

“…Meintrup et al [9] proposed a model in the general context of antiferromagnetism and superconductivity in which nearest neighbour singlet pairing interaction was shown to accommodate both SC and AF states and their coexistence in certain range of parameters. These authors, and several others before them [10,11], showed that it is not necessary to have strong on-site repulsion to generate AF LRO. Correlated models with extended range of interactions can produce AF LRO and SC as well.…”

“…Using a mean-field analysis, these authors studied the coexistence of different singlet SC and AF LRO states in their model. Related extended range models have been studied by numerical methods [10] and mean-field [11] theory earlier, although a detailed study with the possibility of several SC symmetries and AF order have not been undertaken.…”