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Thisted, U.; Nyhus, J.; Suzuki, Takashi; Hori, J.; Fossheim, K.

doi:10.1103/physrevb.67.184510

Cited by 7 publications

(2 citation statements)

References 14 publications

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“…24 Diamagnetism above T c in ac susceptibility has already been reported in almost optimally doped La 2−x Sr x CuO 4 in the same geometry as the one in the present investigation. 25 Their thermal investigations have confirmed that the source of the signal is the transverse fluctuations of the phase of the order parameter, as has been predicted by Emery and Kivelson. 26,27 An attempt to understand the above experimental data has to be based on the changes induced by Pr into the YBa 2 Cu 3 O 7−␦ cuprate, as well as the NMR, SR, and neutron-scattering data available for other superconducting cuprates at the edge of the superconducting to Mott insulator transition.…”

Section: Resultssupporting

confidence: 64%

Magnetic response ofY0.47Pr0.53Ba2Cu3O7−

et al. 2006

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The magnetic response of the strongly underdoped Y 0.47 Pr 0.53 Ba 2 Cu 3 O 7−␦ was investigated. We found the presence of superconducting and magnetic orders deep into the paramagnetic state, up to 200 K, which manifest as diamagneticlike response and hysteresis, respectively. We propose that the main source of irreversibility in this T range is the softening and melting of the glassy state into a viscous liquid of entities that behave like superparamagnetic particles with antiferromagnetic cores.

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Section: Resultssupporting

confidence: 64%

Magnetic response ofY0.47Pr0.53Ba2Cu3O7−

et al. 2006

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“…Further, the flux penetration cannot explain the absorption, Imχ(T ), unless the λ(T ) ≈ R. And the dropped parts of dispersion on La below T c in weak fields are puzzling at all. We note that similar dropped parts were observed also in weak fields on La 2−x Sr x CuO 4 [6]. La is ordinary regarded as a type I superconductor.…”

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confidence: 50%

Susceptibility of Superconductors via Scattering Approach

et al. 2004

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The measurement of magnetic properties of superconductors is usually understood in context with flux penetration length and in case of type-II superconductors also with vortex matter. We investigate the behavior of superconductors in very weak magnetic fields, typically µ0H < 1µT, near the critical temperature. The aim is to explore the details of SN transition and phase diagram (B, T ) of vortex matter in extreme type-II superconductors like cuprates. The data recorded on HTS, even if extensively challenged with theory, are hard to understand as a vortex matter behavior. On the other hand, interpretation on the basis of electron conductivity arising from electron scattering is consistent even with data obtained by x-ray diffraction, photoemission, tunnelling spectroscopy and specific heat. PACS : 74.25.Fy, 74.25.Ha,In type-I superconductors, like Pb or Ga which are "good" BCS superconductors, the superconducting-normal (SN) transition measured by the ac susceptibility in weak magnetic fields is very sharp. In pure (6N) long thin Ga single crystal it is 90% complete in a temperature interval of 2×10 −6 K [1]. On the other hand, the magnetic properties of type-II superconductors, particularly of cuprates which are extreme type II, are expected to be strongly affected by thermodynamic fluctuations in the vicinity of the critical temperature T ≈ T c . Fluctuations should considerably broaden the transition and influence the phase diagram (B, T ) of vortex matter [2]. However, recent low field high-resolution magnetic measurements show a distinct character of SN transition in conventional BCS superconductors and cuprates [3]. Since the transition shape depends on the sample geometry (demagnetization * ) Presented at 12

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