2002/08/30 by Sergey V. Barabash, S. V. Barabash, D. Stroud +1 · 12 citations
Earth and Planetary Sciences · Physics and Astronomy · #Absorption (acoustics) #Advanced Condensed Matter Physics #Condensed matter physics #High-pressure geophysics and materials #Optics #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Quasiparticle #Superconductivity #Superfluidity #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.67.144506
published in Physical review. B, Condensed matter 67(14) (American Physical Society)
arxiv created 2002/08/30 · openalex publication_date 2003/04/11 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We discuss the low-frequency absorption arising from quenched inhomogeneity in the superfluid density \ensuremathρs of a model superconductor. Such inhomogeneities may arise in a high-Tc superconductor from a wide variety of sources, including quenched random disorder and static charge density waves such as stripes. Using standard classical methods for treating randomly inhomogeneous media, we show that both mechanisms produce additional absorption at finite frequencies. For a two-fluid model with weak mean-square fluctuations 〈(\ensuremathδ\ensuremathρs)2〉 in \ensuremathρs and a frequency-independent quasiparticle conductivity, the extra absorption has oscillator strength proportional to the quantity 〈(\ensuremathδ\ensuremathρs)2〉/\ensuremathρs, as observed in some experiments. Similar behavior is found in a two-fluid model with anticorrelated fluctuations in the superfluid and normal fluid densities. The extra absorption typically occurs as a Lorentzian centered at zero frequency. We present simple model calculations for this extra absorption under conditions of both weak and strong fluctuations. The relation between our results and other model calculations is briefly discussed, and their possible relation to experiment is also discussed.