Advances in Superconductivity XII pp 188-190 | Cite as
Charge and Spin Dynamics in Spin-Ladder Sr14Cu24O41 Investigated by Raman Scattering
Abstract
We report on Raman scattering study of changes in the phonon spectrum and low-energy electronic excitations for Sr14Cu24O41. From the polarization and Ca-doping dependence, and from a comparison with previous reports on isostructural compounds, we identify the Raman-allowed modes within the simple structure, consisting of two orthorhombic CuO subcells. At low temperatures, the spectra exhibit a number of normally forbidden phonons as well as additional low-energy excitations. For T < ~200 K, we observe a large loss of low-energy spectral weight that linked to changes in the linewidth of the 246-cm-1 phonon. These effects, analogous to the pseudogap effect in the high-Tc cuprates, can be correlated with recentiy reported resistivity experiments that show the pair formations in the ladders for T< ~-200 K.
Keywords
Sr14-x.CaxCu24O41 Spin-ladder system Raman scattering PseudogapPreview
Unable to display preview. Download preview PDF.
References
- 1.M. Uehara, T. Nagata, J. Akimitsu, H. Takahashi, N. Mori, and K. Kinoshita, J. Phys. Soc. Jpn. 65, 2764–2767 (1996).ADSCrossRefGoogle Scholar
- 2.E. Dagoto and T. M. Rice, Science 271, 618–623 (1996).ADSCrossRefGoogle Scholar
- See e.g., C. Thomsen, in“Light Scattering in Solids VI“edited by M. Cardona and G. Güntherodt, Springer-Verlage, Berlin (1991 pp. 285–359.CrossRefGoogle Scholar
- 4.M.V. Abrashev, C. Thomsen, and M. Surtchev, Physica C 280, 297–303 (1997).ADSCrossRefGoogle Scholar
- 5.T. Noji, K. Kakimoto, and Y. Koike, Jpn. J. Appl. Phys. 37, 100–101 (1998).ADSCrossRefGoogle Scholar
- M. Yoshida, S. Tajima, N. Koshizuka, S. Tanaka, S. Uchida, and S. Ishibashi, Phys. Rev. B 44, 11997–12002(1991).ADSCrossRefGoogle Scholar
- 7.T. Adachi, K. Shiota, M. Kato, T. Noji, Y. Koike, Solid State Commun. 105, 639–642 (1998) 639.Google Scholar
- 8.R. Nemetschek, M. Opel, C. Hoffmann, P. F. Müller, R. Hackl, H. Berger, L. Forró, A. Erb, and E. Walker, Phys. Rev. Lett. 78, 4837–4840 (1997).ADSCrossRefGoogle Scholar
- 9.M. Käll, A. P. Litvinchuk, L. Börjesson, P. Berastegui, and L.-G. Johansson, Phys. Rev. B 53, 3566–3572 (1996).ADSCrossRefGoogle Scholar
- 10.R. S. Eccleston, M. Uehara, J. Akimitsu, H. Eisaki, N. Motoyama, and S. Uchida, Phys. Rev. Lett. 81, 1702–1705 (1998)ADSCrossRefGoogle Scholar