|
Hoffman |
Lab |
J.E. Hoffman,1 E.W.
Hudson,1,2* K.M. Lang,1
V. Madhavan,1 H. Eisaki,3§
S. Uchida,3 J. C. Davis1,2
1Department of Physics, University of
California,
Berkeley, California 94720-7300, USA
2Materials Sciences Division, Lawrence
Berkeley National Laboratory, Berkeley, CA 94720,
USA
3Department of Superconductivity,
University of Tokyo, Yayoi, 2-11-16 Bunkyo-ku, Tokyo 113-8656,
Japan
*Present address: Department of
Physics, Massachusetts Institute of Technology, Cambridge,
MA 02139-4307
§ Present addresses: Department of
Applied Physics, Stanford University, Stanford, Califronia
94305-4060, USA
Science Volume 295 466-469 (18 January 2002).
Scanning tunneling microscopy is used to image the additional quasi-particle states generated by quantized vortices in the high critical temperature superconductor Bi2Sr2CaCu2O8+x. They exhibit a copper-oxygen bond-oriented "checkerboard" pattern, with four unit cell (4a0) periodicity and a ~30 angstrom decay length. These electronic modulations may be related to the magnetic feld-induced, 8a0 periodic, spin density modulations with decay length ~70 angstroms recently discovered in La1.84Sr0.16CuO4. The proposed explanation is a spin density wave localized surrounding each vortex core. General theoretical principles predict that, in the cuprates, a localized spin modulation of wavelength L should be associated with a corresponding electronic modulation of wavelength L/2, in good agreement with our observations.
[full text] [pdf] [email for pdf]
You can read also read the Perspective article
about this paper by Subir Sachdev and Shou-Cheng Zhang:
"Tuning Order in Cuprate Superconductors"
Science 295,
452-454 (18 January 2002).