Quasi-point versus point nodes in Sr2RuO4, the case of a flat tight binding γ sheet

Abstract

We perform a numerical study of the unitary regime as a function of disorder concentration in the imaginary part of the elastic scattering cross-section for the compound Sr2RuO4 in the flat band non-disperse limit. By using a self-consistent tight binding (TB) method, we find a couple of families of Wigner probabilistic functions that help to explain macroscopically the distribution between Fermion dressed quasiparticles and Cooper pairs, and also the position of nodes in the order parameter for Sr2RuO4. Therefore, we are able to show that a TB model for the FS γ-sheet, numerically shows 4 point nodes in a flat γ sheet limit, or 4 quasi-point nodes for strong dispersion γ sheet limit in the reduced phase scattering space (RPS).

A Tale of the Scattering Lifetime and the Mean Free Path

“…From Figure 2, it can be observed for example, that only for Γ + = 0.05 meV there is a noticeable change in slope around the frequency value of 1.4 meV (T c for this compound when samples are clear is around 1.5 Kelvin). The other dressed curves show a smooth minimum displaced to higher frequencies [31].…”

“…To complement this, some numbers for the case where Sr 2 RuO 4 has point nodes is also showed in the third column of Table 1 [31]. The parameter for the Fermi energy is now bigger and close to the zero value (ε F = -0.04 meV), but the other four TB parameters remain equal to those used in the quasinodal case.…”

“…. Therefore, it is important to recall that the Fermi energy ε F enters as a parameter in the function f n , and that the consequence of increasing the number of dressed fermion quasiparticles in the system results in an increase of the Fermi energy [32] as we do to obtain point-nodes in strontium ruthenate [31]. Despite strontium ruthenate continues to be part of an intense discussion with respect to its OP as expressed recently in Curtis M, et al [33], for the point nodes triplet model in the unitary collision regime, Figure 2 shows the behavior of the function ( )…”

“…with parameters: D 0 = 1.0 meV, ε F = -0.04 meV, c = 0, t = 0.4 meV and varying Γ + ≈ (0.05-0.40) meV from dilute to optimal [31]. From Figure 2, it can be observed for example, that only for Γ + = 0.05 meV there is a noticeable change in slope around the frequency value of 1.4 meV (T c for this compound when samples are clear is around 1.5 Kelvin).…”

A Tale of the Scattering Lifetime and the Mean Free Path

“…. Therefore, it is important to recall that the Fermi energy F enters as a parameter in the function fn, and that the consequence of increasing the number of dressed fermion quasiparticles in the system results in an increase of the Fermi energy [33] as we do to obtain point-nodes in strontium ruthenate [31]. Despite strontium ruthenate continues to be part of an intense discussion with respect to its OP as expressed recently in [37], for the point nodes triplet model in the unitary collision regime, Fig.…”