Large Dynamical Fluctuations in the Microwave Conductivity of YBa{sub {bold 2}} Cu{sub {bold 3}}O{sub {bold 7{minus}}}{ital {bold {delta}}} above {ital T{sub c}}

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.77.4438· OSTI ID:397676

Booth, J C; Wu, D H; Qadri, S B; Skelton, E F; Osofsky, M S; Pique, A; Anlage, S M ^[1]

---

1. Center for Superconductivity Research, Department of Physics, University of Maryland, College Park, Maryland 20742-4111 (United States)

We report a systematic investigation of dynamical fluctuation effects in the frequency-dependent microwave conductivity (45 MHz{endash}45 GHz) of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} thin films for {ital T}{approx_gt}{ital T}{sub {ital c}}. Our measurements directly yield a dynamical critical exponent {ital z} in the range 2.3{endash}3.0, and the fluctuation lifetime {tau}{sup fl}, which diverges more quickly than Gaussian theory predicts as the temperature approaches {ital T}{sub {ital c}} from above, independent of sample quality. In addition, both the temperature and the frequency dependence of the fluctuation conductivity {sigma}{sup fl} exhibit scaling behavior for temperatures 1{endash}2 K above {ital T}{sub {ital c}}, and can be collapsed onto the same universal curve. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 397676
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 21 Vol. 77; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
COPPER OXIDES
CRITICAL EXPONENTS
ELECTRIC CONDUCTIVITY
FLUCTUATIONS
FREQUENCY DEPENDENCE
HIGH-TC SUPERCONDUCTORS
MICROWAVE RADIATION
SCALING LAWS
TEMPERATURE DEPENDENCE
YTTRIUM OXIDES