TY - JOUR
T1 - Phonon softening in HgBa2CuO4+δ and MgB 2
AU - Uchiyama, H.
AU - Baron, A. Q.R.
AU - Tsutsui, S.
AU - Tanaka, Y.
AU - Ishikawa, D.
AU - Lee, S.
AU - Hu, W. Z.
AU - Yamamoto, A.
AU - Heid, R.
AU - Bohnen, K. P.
AU - Ishikawa, T.
AU - Tajima, S.
AU - Endoh, Y.
N1 - Funding Information:
This work was supported by the New Energy and Industrial Technology Department Organization (NEDO) as Collaborative Research and Development of Fundamental Technologies for Superconductivity Applications. The synchrotron radiation experiments were performed at the BL35XU in the SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal Nos. 2002A0559, 2002B0287, 2002B0594 and 2003A0555). H. U. and S. Tsutsui acknowledge financial support by the JSPS.
PY - 2006/1
Y1 - 2006/1
N2 - Phonon dispersion of two superconductors was studied with using inelastic X-ray scattering. In MgB2, which is thought as a Eliashberg type superconductor, the phonon dispersion shows softening of the E2g mode around Γ in the [100] direction, in excellent agreement with ab initio calculations. It supports the idea that this phonon gives main contribution to the superconductivity. In HgBa2CuO4+δ, on the other hand, which is a good candidate for phonon measurement in the high-Tc cuprates, the dispersion shows anomalous softening of the bond stretching mode at q∼0.3 in the [100] direction. The softening does not agree with shell model calculations well, suggesting existence of spatial charge fluctuation with periodicity of q∼0.3.
AB - Phonon dispersion of two superconductors was studied with using inelastic X-ray scattering. In MgB2, which is thought as a Eliashberg type superconductor, the phonon dispersion shows softening of the E2g mode around Γ in the [100] direction, in excellent agreement with ab initio calculations. It supports the idea that this phonon gives main contribution to the superconductivity. In HgBa2CuO4+δ, on the other hand, which is a good candidate for phonon measurement in the high-Tc cuprates, the dispersion shows anomalous softening of the bond stretching mode at q∼0.3 in the [100] direction. The softening does not agree with shell model calculations well, suggesting existence of spatial charge fluctuation with periodicity of q∼0.3.
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U2 - 10.1016/j.jpcs.2005.10.072
DO - 10.1016/j.jpcs.2005.10.072
M3 - Article
AN - SCOPUS:33645093479
SN - 0022-3697
VL - 67
SP - 294
EP - 297
JO - Journal of Physics and Chemistry of Solids
JF - Journal of Physics and Chemistry of Solids
IS - 1-3
ER -