Zobrazeno 1 - 10
of 210
pro vyhledávání: '"Ammerahl, U."'
Publikováno v:
Phys. Rev. B 90, 224516 (2014)
We present a polarization-dependent infrared reflectivity study of the spin-ladder compound Sr$_{2.5}$Ca$_{11.5}$Cu$_{24}$O$_{41}$ under pressure. The optical response is strongly anisotropic, with the highest reflectivity along the ladders/chains (\
Externí odkaz:
http://arxiv.org/abs/1411.7590
Autor:
Baek, S. -H., Hammel, P. C., Hücker, M., Büchner, B., Ammerahl, U., Revcolevschi, A., Suh, B. J.
Publikováno v:
Phys. Rev. B 87, 174505 (2013)
139La NMR and relaxation measurements have been performed on La{1.8-x}Eu{0.2}Sr{x}CuO{4} (x = 0.13 and 0.2) single crystals. The temperature dependence of the 139La NMR spectra in all the structural phases (HTT -> LTO -> LTT) reveals the non-vanishin
Externí odkaz:
http://arxiv.org/abs/1303.6426
We have studied the spin anisotropy in spin-singlet ground state compounds and the magnetic chirality, as measured by inelastic polarized neutron scattering techniques, in the chain-sublattice of Sr14Cu24O41. In-plane and out of plane magnetic fluctu
Externí odkaz:
http://arxiv.org/abs/cond-mat/0606598
Autor:
Choi, K. -Y., Grove, M., Lemmens, P., Fischer, M., Güntherodt, G., Ammerahl, U., Büchner, B., Dhalenne, G., Revcolevschi, A., Akimitsu, J.
We report inelastic light scattering experiments in the spin-chain and ladder system Sr_14-xCa_xCu_24O_41. A depletion of an electronic background is observed for 0 < x < 5 at low temperatures and with light polarization both parallel to the leg and
Externí odkaz:
http://arxiv.org/abs/cond-mat/0601203
Publikováno v:
Phys. Rev. B 72, 184406 (2005)
We report on magnetisation measurements of Sr14-xCaxCu24O41, with 0 <= x <= 12, in magnetic fields up to 16 T. The low temperature magnetic response of the CuO2 spin chains changes strongly upon doping. For x = 0, the ground state with nearly indepen
Externí odkaz:
http://arxiv.org/abs/cond-mat/0511110
Autor:
Klingeler, R., Buchner, B., Choi, K. -Y., Kataev, V., Ammerahl, U., Revcolevschi, A., Schnack, J.
Publikováno v:
Phys. Rev. B 73, 014426 (2006)
We study the magnetism of the hole doped CuO2 spin chains in Sr14Cu24O41 by measuring the Electron Spin Resonance (ESR) and the static magnetization M in applied magnetic fields up to 14 T. In this compound, the dimerized ground state and the charge
Externí odkaz:
http://arxiv.org/abs/cond-mat/0508626
Publikováno v:
Phys. Rev. B 73, 104407 (2006)
The magnon thermal conductivity $\kappa_{\mathrm{mag}}$ of the spin ladders in $\rm Sr_{14}Cu_{24-x}Zn_xO_{41}$ has been investigated at low doping levels $x=0$, 0.125, 0.25, 0.5 and 0.75. The Zn-impurities generate nonmagnetic defects which define a
Externí odkaz:
http://arxiv.org/abs/cond-mat/0506595
Autor:
Huecker, M., Kataev, V., Pommer, J., Ammerahl, U., Revcolevschi, A., Tranquada, J. M., Buechner, B.
Publikováno v:
Phys. Rev. B 70, 214515 (2004)
The Cu spin magnetism in La2-x-yEuySrxCuO4 (x<=0.17; y<=0.2) has been studied by means of magnetization measurements up to 14 T. Our results clearly show that in the antiferromagnetic phase Dzyaloshinsky-Moriya (DM)superexchange causes Cu spin cantin
Externí odkaz:
http://arxiv.org/abs/cond-mat/0309461
Publikováno v:
Phys. Rev. Lett. 93, 027005 (2004)
The magnon thermal conductivity $\kappa_{\mathrm{mag}}$ of the hole doped spin ladders in $\rm Sr_{14-x}Ca_xCu_{24}O_{41}$ has been investigated at low doping levels $x$. The analysis of $\kappa_{\mathrm{mag}}$ reveals a strong doping and temperature
Externí odkaz:
http://arxiv.org/abs/cond-mat/0309232
Publikováno v:
Phys. Rev. B 68, 184517 (2003)
Results of in-plane and out-of-plane thermal conductivity measurements on $\rm La_{1.8-x}Eu_{0.2}Sr_xCuO_4$ ($0\leq x\leq0.2$) single crystals are presented. The most characteristic features of the temperature dependence are a pronounced phonon peak
Externí odkaz:
http://arxiv.org/abs/cond-mat/0305321