Optical spectral weight transfer in highTc cuprates

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Optical spectral weight transfer in high-Tc
cuprates
Erik van Heumen F. Carbone, A.B. Kuzmenko, D.
van der Marel University of Geneva M.
Greven Stanford University C.C. Homes Brookhaven
Nat. Laboratory S.V Dordevic Akron University
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High Tc phase diagram
"Strange metal"
Temperature
Pseudo - gap
Fermi liquid ?
AF
Stripes?
d-wave SC
SG
Doping concentration
3
Experimental technique
Reflectivity
Ellipsometry
Hg-1201 Tc97 K
Hg-1201 Tc97 K
Multi-oscillator variational routine Kuzmenko,
Rev. Sci. Instr. (2005)
?(?), e(?)
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Optical properties of Hg-1201
Tc97 K
// Cu-O plane
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Bands and optical conductivity
Free charge (Drude)
interband
s1
?
Total SW
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(No Transcript)
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Temperature
Pseudo-gap
Fermi liquid ?
AF
d-wave SC
Doping concentration
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SW transfer at optimal doping
Science 295, 2239-2241 (2002).
Unpublished
PRB 74, 24502 (2006)
three layers
two layers
one layer
?sW 0.5 0.2 meV per Cu
?sW 0.65 0.1 meV per Cu
?sW 1.1 0.1 meV per Cu
E. van Heumen
H.J.A. Molegraaf
F. Carbone
?sW WS(?c, 20 K) - WN(?c, T?20 K)
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Doping dependence, Bi-2212
F. Carbone et al., Phys. Rev. B 74, 064510 (2006)

First evidence of sign reversal in OvD Bi2212
G. Deutscher, A. F. Santander-Syro and N.
Bontemps, PRB (2005).
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Bi-2212 Kinetic energy and phase diagram
Tc
Another explanation CDMFT on t-J model gives
sign change K. Haule, G. Kotliar, cond-mat
0601478
Trend for Bi-2212 also observed by G. Deutscher
et al, PRB (2005).
Boris et al, Science (2004) Find opposite sign
for optimally doped YBCO
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Hole kinetic energy in the t-J model
CDMFT of the t-J model.
F. Carbone et al., Phys. Rev. B 74, 064510 (2006)
G. Kotliar C. Haule cond-mat0601478
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Conclusions
In agreement with G. Deutscher, A. F.
Santander-Syro , N. Bontemps, PRB 72, 092504
(2005).