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Title: Distinct Fermi-Momentum-Dependent Energy Gaps in Deeply Underdoped Bi-2212

Abstract

No abstract prepared.

Authors:
; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
897753
Report Number(s):
SLAC-REPRINT-2006-192
TRN: US200705%%242
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Science 314:1910-1913,2006
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ENERGY GAP; BISMUTH OXIDES; STRONTIUM OXIDES; CALCIUM OXIDES; COPPER OXIDES; Other,OTHER

Citation Formats

Tanaka, K., Lee, W.S., Lu, D.H., Fujimori, A., Fujii, T., Risdiana, Terasaki, I., Scalapino, D.J., Devereaux, T.P., Hussain, Z., Shen, Z.X., and /Stanford U., Appl. Phys. Dept. /SLAC, SSRL /LBNL, ALS /Tokyo U. /Waseda U. /UC, Santa Barbara /Waterloo U. /British Columbia U. Distinct Fermi-Momentum-Dependent Energy Gaps in Deeply Underdoped Bi-2212. United States: N. p., 2007. Web.
Tanaka, K., Lee, W.S., Lu, D.H., Fujimori, A., Fujii, T., Risdiana, Terasaki, I., Scalapino, D.J., Devereaux, T.P., Hussain, Z., Shen, Z.X., & /Stanford U., Appl. Phys. Dept. /SLAC, SSRL /LBNL, ALS /Tokyo U. /Waseda U. /UC, Santa Barbara /Waterloo U. /British Columbia U. Distinct Fermi-Momentum-Dependent Energy Gaps in Deeply Underdoped Bi-2212. United States.
Tanaka, K., Lee, W.S., Lu, D.H., Fujimori, A., Fujii, T., Risdiana, Terasaki, I., Scalapino, D.J., Devereaux, T.P., Hussain, Z., Shen, Z.X., and /Stanford U., Appl. Phys. Dept. /SLAC, SSRL /LBNL, ALS /Tokyo U. /Waseda U. /UC, Santa Barbara /Waterloo U. /British Columbia U. Tue . "Distinct Fermi-Momentum-Dependent Energy Gaps in Deeply Underdoped Bi-2212". United States. doi:.
@article{osti_897753,
title = {Distinct Fermi-Momentum-Dependent Energy Gaps in Deeply Underdoped Bi-2212},
author = {Tanaka, K. and Lee, W.S. and Lu, D.H. and Fujimori, A. and Fujii, T. and Risdiana and Terasaki, I. and Scalapino, D.J. and Devereaux, T.P. and Hussain, Z. and Shen, Z.X. and /Stanford U., Appl. Phys. Dept. /SLAC, SSRL /LBNL, ALS /Tokyo U. /Waseda U. /UC, Santa Barbara /Waterloo U. /British Columbia U.},
abstractNote = {No abstract prepared.},
doi = {},
journal = {Science 314:1910-1913,2006},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 16 00:00:00 EST 2007},
month = {Tue Jan 16 00:00:00 EST 2007}
}
  • We used angle-resolved photoemission spectroscopy applied todeeply underdoped cuprate superconductors Bi2Sr2Ca(1-x)YxCu2O8 (Bi2212)to reveal the presence of two distinct energy gaps exhibiting differentdoping dependence. One gap, associated with the antinodal region where nocoherent peak is observed, increased with underdoping, a behavior knownfor more than a decade and considered as the general gap behavior in theunderdoped regime. The other gap, associated with the near-nodal regimewhere a coherent peak in the spectrum can be observed, did not increasewith less doping, a behavior not previously observed in the singleparticle spectra. We propose a two-gap scenario in momentum space that isconsistent with other experiments andmore » may contain important informationon the mechanism of high-transition temperaturesuperconductivity.« less
  • The improved resolution of laser-based angle-resolved photoemission spectroscopy (ARPES) allows reliable access to fine structures in the spectrum. We present a systematic, doping-dependent study of a recently discovered low-energy kink in the nodal dispersion of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} (Bi-2212), which demonstrates the ubiquity and robustness of this kink in underdoped Bi-2212. The renormalization of the nodal velocity due to this kink becomes stronger with underdoping, revealing that the nodal Fermi velocity is non-universal, in contrast to assumed phenomenology. This is used together with laser-ARPES measurements of the gap velocity, v{sub 2}, to resolve discrepancies with thermal conductivity measurements.
  • New tunneling data are reported in Bi{sub 2}Sr {sub 2}CaCu{sub 2}O{sub 8+{delta}} which show quasiparticle excitation gaps, {Delta}, reaching values as high as 60thinspthinspmeV for underdoped crystals with T{sub c}=70 K . These energy gaps are nearly 3thinspthinsptimes larger than those of overdoped crystals with similar T{sub c} . Despite the large differences in gap magnitude, the tunneling spectra display qualitatively similar characteristics over the entire doping range. Detailed examination of the spectra, including the Josephson I{sub c}R{sub n} product measured in break junctions, indicates that these energy gaps are predominantly of superconducting origin. {copyright} {ital 1999} {ital The Americanmore » Physical Society}« less
  • Cited by 2
  • Electron-electron interactions in overdoped Bi-2212 are studied by inelastic light scattering. The optimally to slightly overdoped compounds exhibit two-magnon excitations with a dependence on the incident photon energy typical for doped antiferromagnets. For more overdoped samples, no two-magnon excitation is visible, indicating an antiferromagnetic correlation below twice the lattice parameter. In the same samples, the gap excitation shows a resonance similar to the two-magnon excitation. We interpret our results as a development towards a correlated Fermi liquid when the doping is increased. {copyright} {ital 1999} {ital The American Physical Society}