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Possibility of an ordered state of spins and holes in single-crystalLa2−xSrxWatanabe1, Aoyama2, Akoshima3 et al. 2000Phys. Rev. BSelf Cite21280View full textAdd to dashboardCite

“…Actually, Kakinuma et al reported anomalous behavior of the transport phenomena with a little suppression of the supeconductivity in Zn-substituted polycrystalline samples of La 2Ϫx Sr x Cu 1Ϫy Zn y O 4 ͑LSCZO͒ around xϭ0.22, suggesting a possibility of the existence of an ordered state of spins and holes in the overdoped region. 12,13 Moreover, Kawamata et al 14 recently developed the sample quality of LSCZO and successfully grew a homogeneous single crystal with x ϭ0.21 and yϭ0.01, exhibiting no bulk superconductivity at low temperatures at least above 2 K. They confirmed that bulk superconductivity appeared again as the Sr-doping level shifted to the lighter or heavier side from xϭ0.21 in the Zn-substituted single crystals with yϭ0.01. This fact means that the suppression of superconductivity in the Znsubstituted single crystal occurs singularly at xϭ0.21.…”

“…This difference can be reasonably explained by the model that the dynamical stripe correlations of spins and holes are pinned by the substituted Zn and stabilized being accompanied by the suppression of the Cu-spin fluctuations. [11][12][13][14]16 As a result, it is concluded that the slowing-down behavior of the Cu-spin fluctuations is not due to the Zn-substitution effect but to the intrinsic behavior at xϭ0.21 in LSCO. That is to say, the Cu-spin correlation is enhanced at xϭ0.21 and the Zn substitution leads to a static order of Cu spins.…”

Giant suppression of superconductivity atx=0.21in the Zn-substitutedLa2−xAdachi1, Noji2, Koike3 2000Phys. Rev. BSelf Cite401250View full textAdd to dashboardCite

“…An analogous local minimum of T c has also been observed at xϭ0.22 in the nonsubstituted polycrystalline samples, though the x value is slightly different from 0.21. 17,18 To summarize the experimental results, a little suppression of superconductivity has been found at xϭ0.21 in the non-Zn-substituted single crystals, and a giant suppression of superconductivity has been found at xϭ0.21 in the 1% Znsubstituted single-crystals. In the 1% Zn-substituted single crystal with xϭ0.21, moreover, the temperature dependences of ab and c have been found to be anomalous, though they are normal in the non-Zn-substituted single crystal with x ϭ0.21.…”

“…Furthermore, it has been found that the anomalies become marked through the partial substitution of Zn or Ga for Cu and that the anomalies are not related to the structural phase transition between the tetragonal high-temperature ͑THT͒ phase ͑space group: I4/mmm) and the orthorhombic mid-temperature ͑OMT͒ phase ͑space group: Bmab͒. 17,18 So, we have pointed out that probably an order of spins and/or holes, such as the stripe order, is formed or fluctuates around xϭ0. 22 in La 2Ϫx Sr x CuO 4 , though this x value is neither the simply expected 1/4 nor 1/5.…”

“…This suppression of superconductivity is more striking than that observed in the Zn-or Ga-substituted polycrystalline samples. 17,18 This may be due to better homogeneity of the Sr concentration in the single crystals than in the polycrystalline samples. It is also remark- able that a local minimum of T c is observed at xϭ0.21 in the non-Zn-substituted single crystals as well.…”