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تسجيل مستخدم جديدProbing active/passive bands by quasiparticle interference in Sr$_{2}$RuO$_{4}$
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The quasiparticle interference (QPI) in Sr$_{2}$RuO$_{4}$ is theoretically studied based on two different pairing models in order to propose an experimental method to test them. For a recently proposed two-dimensional model with pairing primarily from the $gamma$ band, we found clear QPI peaks evolving with energy and their locations can be determined from the tips of the constant-energy contour (CEC). On the other hand, for a former quasi-one-dimensional model with pairing on the $alpha$ and $beta$ bands, the QPI spectra are almost dispersionless and may involve off-shell contributions to the scatterings beyond the CEC. The different behaviors of the QPI in these two models may help to resolve the controversy of active/passive bands and whether Sr$_{2}$RuO$_{4}$ is a topological superconductor.
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Sr$_{2}$RuO$_{4}$ (SRO) is the prime candidate for chiral $p$-wave superconductor with critical temperature $T_{c}(SRO)sim$1.5 K. Chiral domains with opposite chiralities $p_{x}pm ip_{y}$ were proposed, but yet to be confirmed. We measure the field d
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Sr$_{2}$RuO$_{4}$ is one of the most promising candidates of a topological superconductor with broken time-reversal symmetry, because a number of experiments have revealed evidences for a spin-triplet chiral $p$-wave superconductivity. In order to cl
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The single-layered ruthenate Sr$_2$RuO$_4$ has attracted a great deal of interest as a spin-triplet superconductor with an order parameter that may potentially break time reversal invariance and host half-quantized vortices with Majorana zero modes.
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