BCS to Bose-Einstein crossover phase diagram at zero temperature for adx2−y2

Comment on “BCS to Bose-Einstein crossover phase diagram at zero temperature for adx2−y2Perali1, Pieri2, Strinati3 2003Phys. Rev. B6010View full textAdd to dashboardCite

“…The gap parameter at Tϭ0 is, in fact, finite for any nonzero density and coupling, even in the weakcoupling regime, contrary to the results of Soares et al 1 and den Hertog. 2 In systems with dopant impurities, 10 on the other hand, a critical value of the fermion density at Tϭ0 for the onset of d-wave superconductivity is instead possible.…”

“…In Ref. [1], Soares et al analyzed the BCS-BE crossover at T = 0 for d-wave pairing in the attractive Hubbard model, extending the work by den Hertog [2] by including the nextnearest neighbor hopping t ′ in the tight-binding dispersion. As is evident from the insets of Figs.…”

Cooper pairing with finite angular momentum: BCS versus Bose limits

“…Many of these materials present exotic pairing in the form of a superconducting state that breaks the rotational symmetry of the crystal, and they often deviate from BCS theory in several other ways [11]. This led to a resurgence of interest in the BCS to Bose crossover [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], particularly in models with exotic pairing [27][28][29][30][31][32][33]48]. On the other hand, little attention has been paid to the physics of the crossover in the context of the original discussions of exotic pairing [3,4], namely when a central attraction, in a continuum, leads to Cooper pairing with l>0.…”

Evidence for a metallic–like state in the T=0 K phase diagram of a high temperature superconductor

“…On the other hand, the situation for the case of a dwave symmetry of the superconducting order parameter is much more controversial. den Hertog [20] and Soares et al [21] claim that a non-pairing region, metallic-like phase, is present in the phase diagram at low attractive interactions. However, such a claim is in contradiction with the standard d-wave solution of the weak coupling BCS equation, which proves for the continuous model the existence of a superconducting state regardless the value of the attractive interaction between the electrons [22].…”