Search for Competing Order-parameters in Cuprates using FT-STS
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Transcript of Search for Competing Order-parameters in Cuprates using FT-STS
Search for Competing Order-parameters in Cuprates using FT-STS
J. E. Hoffman, K. McElroy, E.W. Hudson, H Eisaki, S. Uchida & J. C. Seamus Davis
Research Support:
Superconductors: other phases?
Conventional, Low Tc High Tc cuprates
Orenstein & Millis, Science 288, 5465
SCAF
H. Kammmerlingh-Onnes,Commun. Phys. Lab. 12, 120 (1911)
superconducting
Fermi liquid
So many proposed phasesthey won’t fit in this small space...
Theory: many proposed phases...
Coexisting SDW/CDWDemler, Sachdev, Zhang, PRL 87, 067202
Franz, et al., condmat/0203219QED3
Varma phaseVarma, PRB 61, R3804
Staggered Flux PhaseKishine, Lee & Wen, PRL 86, 5365
Fractionalized Nodal Liquid:Superconductivity without pairing?
Senthil & Fisher, PRB 62, 7864 (2001)
STRIPESS. White, Zaanen,
Kivelson, Emery, etc.
D-density wave (DDW)Chakravarty, Laughlin, et al.,PRB 63, 094503
SO(5) theoryS.C. Zhang, Science 275, 1089
Theory: many proposed phases...
Background: Common Phenomenology of Vortex Cores in HTSC
0 1200 Å
• I. Maggio-Aprile et al., Phys. Rev. Lett. 75, 2754 (1995)
• S. H. Pan et al., Phys. Rev. Lett. 85, 1536 (2000)
0 500Å0 1000Å
1
0.1
0 15 30 45 60 75Distance from core [Å]
Norm
aliz
ed d
I/dV
ExponentialDecay of
Core State BSCCO
-200 -100 0 100 200V sample [mV]
2
1
dI/dV
[nS]
dI/dV spectra on Bi2Sr2CaCu2O8+x surface in B=7 Tesla
30 nm
7 meV LDOS
Pan, PRL 85,1536 (2000)
560 Å
B = 0 T B = 5 T
Topographies
560 Å
1.1 Å
0 Å
xy
560 Å
B = 0 T B = 5 T
E = 12 meV
560 Å
0.5 nS
0 nS
xy
Reproducibility of vortex data
Raw data: 7 meV LDOS 560 Å x 560 Å
Raw data: 8 meV LDOS 565 Å x 565 Å
0.5% Ni-doped BSCCO 0.6% Zn-doped BSCCO
xyxy
2 pA
0 pA
Vortex-induced LDOS (5 Tesla)
Science 266, 455 (2002)
560 Å
xy
Fourier Transform of Vortex LDOS map
vortex induced LDOS Bi and Cu atoms
Data: Schematic:
Science 266, 455 (2002)
~(1/4,0)
supermodulation
xy
Coexisting SDW/CDW ?