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 La 2-x Ba x CuO 4 Charge & Spin Stripes

LBCO CGO 1 mm Single-Crystal XRD at Low Temperature 360° X-ray window  Intensity ~10 -6 off strongest Bragg Peak  Powder XRD not possible  E=100keV, photons/sec/mm 2 BW5-HASYLAB

High Pressure Beamline at NSLS-II  Single Crystal XRD  4-Circle Diffractometer  Point Detector (2D Detector optional)  Low Temperature  Flux >10 11 –10 12 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 mm 3 30 GPa 25 kg low T not so easy Diamond Anvil Cell mm GPa small beam sample position pressure inhomogeneous ISIS

Yamada et al. JSSC 1989 Bozovic et al. PRL 2002 LSCO thin film LSCO 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 single-crystal HXRD

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. Sr 14 Cu 24 O 41 Abbamonte et al. RSXS oxygen-K edge XRD: Zimmermann et al. PRB 2006

3 GPa 4 GPa 7 GPa NSLS/HASYLAB/NSLSII 100keV Large Volume Pressure Cells for Single-Crystal X-ray Diffraction 100keV Mini Toroid Cell 1 cm

pressure cell: scattering/absorption pressure cell absorption: factor 10

pressure sensor: CuGeO 3 structural distortion at the spin Peierls transition at 14 K

100 keV beamline BW5 at HASYLAB, Hamburg E-range: keV Crystal type: Si/TaSi 2 (100”) Si 1-x Ge x (15”–70”) Our Exp: 35” E-resolution: 600eV at 100keV Flux(photons/s): 2e11/mm 100keV (100mA, 4.5GeV) Spot size: 0.5mm x 0.5mm to 6mm x 6mm Detector: N 2 cooled Ge det. Wiggler: 2Tesla, 17 periods

Competing Order Lattice density (pressure) Charge density (doping) CePd 2 Si 2