Post on 18-Dec-2015
M. Hücker
Manipulating Competing Order with High Pressure
Neutron Scattering Group (CMPMS)
Correlated Electron Systems(Superconductivity, Magnetism, Electronic Order)
High Temperature Superconductors Transition Metal Oxides Ferroelectrics Heavy Fermion Systems Multiferroics
La2-xBaxCuO4
Charge & Spin Stripes
LBCO
CGO
1 mm
Single-Crystal XRD at Low Temperature
36
0° X
-ray w
ind
ow
Intensity ~10-6 off strongest Bragg Peak Powder XRD not possible E=100keV, 2•1011 photons/sec/mm2
BW5-HASYLAB
High Pressure Beamline at NSLS-II
Single Crystal XRD 4-Circle Diffractometer Point Detector (2D Detector optional) Low Temperature Flux >1011–1012 photons/sec on Sample DAC (MAC,Toroid) Sample Centering
M. v. Zimmermann, HASYLAB J. M. Tranquada, G. Xu, Neutron Scattering Group Y. J. Kim, University of Toronto B. Wells, University of Connecticut D. J. Buttrey, University of Delaware C. C. Kao, Z. Zhong, NSLS
NSLS II
Paris Edinburgh Cell
100 mm3
30 GPa 25 kglow T not so easy
Diamond Anvil Cell
0.0001 mm3
100 GPasmall beamsample positionpressure inhomogeneous
ISIS
Yamada et al. JSSC 1989
Bozovic et al. PRL 2002
LSCO thin filmLSCO bulk
Gao et al. PRB 1994
Hg-1223 bulk
Pressure and Superconductivity
Pressure: affects crystal structure and electronic band structure
buckled
flat
Competing order in LBCO
150
200
250
300
350
La2-xBa
xCuO
4
LTO
HTT
Tem
pera
ture
(K
)
0.100 0.125 0.1500
10
20
30
40
50
60
70LTO
++LTT
Pccn
TCO
Tc
TSO
TLT
LTO
Pccn
LTT
Tem
pera
ture
(K
)
hole doping (x)
single-crystalHXRD
Charge Stripes under Pressure
LTT structure
Charge Stripes
Do stripes survive in flat planes when x=1/8?
Hole Crystallization in 2-Leg Ladder
Blumberg et al. Science 2002
Rusydi et al.
Sr14Cu24O41Abbamonte et al.
RSXSoxygen-K edge
XRD: Zimmermann et al. PRB 2006
3 GPa 4 GPa
7 GPa
NSLS/HASYLAB/NSLSII100keV
Large Volume Pressure Cells for Single-Crystal X-ray Diffraction
100keV
Mini Toroid Cell
1 cm
pressure cell: scattering/absorptionpressure cell: scattering/absorption
pressure cell absorption: factor 10
pressure sensor: CuGeO3pressure sensor: CuGeO3
structural distortion at the spin Peierls transition at 14 K
100 keV beamline BW5 at HASYLAB, Hamburg
E-range:60-200 keV
Crystal type:Si/TaSi2 (100”)Si1-xGex (15”–70”)Our Exp: 35”
E-resolution:600eV at 100keV
Flux(photons/s):2e11/mm2 @ 100keV(100mA, 4.5GeV)
Spot size:0.5mm x 0.5mm to6mm x 6mm
Detector:N2 cooled Ge det.
Wiggler:2Tesla, 17 periods