A novel antiproton radial diagnostic based on octupole induced ballistic loss (2008)
Andresen, G. B., Bertsche, W., Bowe, P. D., Bray, C. C., Butler, E., Cesar, C. L., ...
We report results from a novel diagnostic that probes the outer radial profile of trapped antiproton clouds. The diagnostic allows us to determine the profile by monitoring the time-history of...
Compression of Antiproton Clouds for Antihydrogen Trapping (2008)
Andresen, G. B., Bertsche, W., Bowe, P. D., Bray, C. C., Butler, E., Cesar, C. L., ...
Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report the first detailed measurements of the radial manipulation of antiproton clouds, including...
Electron pockets in the Fermi surface of hole-doped high-Tc superconductors (2008)
LeBoeuf, David, Doiron-Leyraud, Nicolas, Levallois, Julien, Daou, R., Hussey, N. E., ...
High-temperature superconductivity occurs as copper oxides are chemically tuned to have a carrier concentration intermediate between their metallic state at high doping and their insulating state at...
Particle Physics Aspects of Antihydrogen Studies with ALPHA at CERN (2008)
Andresen, G. B., Bertsche, W., Bowe, P. D., Bray, C. C., Butler, E., ...
We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERN's Antiproton Decelerator facility. We review the...
Raman study of Twin Free YBa$_2$Cu$_3$O$_{6.5}$ (Ortho-II) Single Crystals (2008)
Iliev, M. N., Hadjiev, V. G., Jandl, S., Boeuf, D. Le, Popov, V. N., Bonn, D., ...
The polarized Raman scattering spectra from freshly cleaved $ab$, $ac$, and $bc$ surfaces of high quality twin free YBa$_2$Cu$_3$O$_{6.5}$ (Ortho-II) single crystals ($T_c$=57.5 K and $\Delta T =...
Relaxation nucléaire de 3He gazeux sur H2 solide (2008)
Lefèvre-Seguin, V., Nacher, P.J., Brossel, J., Hardy, W.N., Laloë, F.
Cet article présente une étude expérimentale détaillée de la relaxation-paroi sur des surfaces de H2 solide d'un gaz dilué de 3He, orienté par pompage optique. La grandeur mesurée dans ces...
Relaxation nucléaire de 3He gazeux sur H2 solide (2008)
Lefèvre-Seguin, V., Nacher, P.J., Brossel, J., Hardy, W.N., Laloë, F.
Cet article présente une étude expérimentale détaillée de la relaxation-paroi sur des surfaces de H2 solide d'un gaz dilué de 3He, orienté par pompage optique. La grandeur mesurée dans ces...
Guikema, J. W., Bluhm, Hendrik, Bonn, D. A., Liang, Ruixing, Hardy, W. N., Moler, K. A.
We report scanning Hall probe microscopy of highly underdoped superconducting YBa_2Cu_3O_{6+x} with T_c ranging from 5 to 15 K which showed distinct flux bundles with less than one superconducting...
Stock, C., Buyers, W. J. L., Yamani, Z., Tun, Z., Birgeneau, R. J., Liang, R., ...
Using neutron scattering we have determined the magnetic structure and fluctuations in the YBa2Cu3O6.35 superconductor (Tc=18 K). The long-range ordered collinear spins of the insulating...
Hossain, M. A., Mottershead, J. D. F., Bostwick, A., McChesney, J. L., Rotenberg, E., Liang, R., ...
The discovery of quantum oscillations in the normal-state electrical resistivity of YBa2Cu3O6.5 provides the first evidence for the existence of Fermi surface (FS) pockets in an underdoped cuprate....
Sonier, J. E., Ilton, M., Pacradouni, V., Kaiser, C. V., Sabok-Sayr, S. A., Ando, Y., ...
We report that in YBa2Cu3Oy and La2-xSrxCuO4 there is a spatially inhomogeneous response to magnetic field for temperatures T extending well above the bulk superconducting transition temperature Tc....
Quantum oscillations and the Fermi surface in an underdoped high-Tc superconductor (2008)
Doiron-Leyraud, Nicolas, Proust, Cyril, LeBoeuf, David, Levallois, Julien, Bonnemaison, Jean-Baptiste, Liang, Ruixing, ...
Despite twenty years of research, the phase diagram of high transition- temperature superconductors remains enigmatic. A central issue is the origin of the differences in the physical properties of...
de Haas-van Alphen oscillations in the underdoped cuprate YBa$_2$Cu$_3$O$_{6.5}$ (2007)
Jaudet, C., Vignolles, D., Audouard, A., Levallois, J., LeBoeuf, D., Doiron-Leyraud, N., ...
The de Haas-van Alphen effect was observed in the underdoped cuprate YBa$_2$Cu$_3$O$_{6.5}$ via a torque technique in pulsed magnetic fields up to 59 T. Above an irreversibility field of $\sim$30 T,...
Xia, Jing, Schemm, Elizabeth, Deutscher, G., Kivelson, S. A., Bonn, D. A., Hardy, W. N., ...
Polar Kerr effect in the high-Tc superconductor \YBCO was measured at zero magnetic field with high precision using a cyogenic Sagnac fiber interferometer. We observed non-zero Kerr rotations of...
Sonier, J. E., Callaghan, F. D., Ando, Y., Kiefl, R. F., Brewer, J. H., Kaiser, C. V., ...
Highly disordered magnetism confined to individual weakly interacting vortices is detected by muon spin rotation in two different families of high-transition-temperature superconductors, but only in...
Sonier, J. E., Sabok-Sayr, S. A., Callaghan, F. D., Kaiser, C. V., Pacradouni, V., Brewer, J. H., ...
We report on muon spin rotation measurements of the internal magnetic field distribution n(B) in the vortex solid phase of YBa2Cu3Oy (YBCO) single crystals, from which we have simultaneously...
Antiferromagnetic correlations near the lower edge of superconducting dome in YBCO6+x (2007)
Yamani, Z., Buyers, W. J. L., Wang, F., Liang, R., Bonn, D., ...
Neutron scattering from high-quality YBCO6.334 single crystals with a T$_c$ of 8.4 K shows that there is no coexistence with long-range antiferromagnetic order at this very low, near-critical doping...
Towards Antihydrogen Confinement with the ALPHA Antihydrogen Trap (2007)
Fujiwara, M. C., Andresen, G., Bertsche, W., Boston, A., Bowe, P. D., Cesar, C. L., ...
ALPHA is an international project that has recently begun experimentation at CERN's Antiproton Decelerator (AD) facility. The primary goal of ALPHA is stable trapping of cold antihydrogen atoms with...
Evidence for decay of spin-waves above the pseudogap in underdoped YBa2Cu3O6.35 (2007)
Stock, C., Cowley, R. A., Buyers, W. J. L., Coldea, R., Broholm, C., Frost, C. D., ...
The magnetic spectrum at high-energies in heavily underdoped YBa$_{2}$Cu$_{3}$O$_{6.35}$ (T$_{c}$=18 K) has been determined throughout the Brillouin zone. At low-energy the scattering forms a cone of...
Buyers, W. J. L., Stock, C., Yamani, Z., Birgeneau, R. J., Liang, R., Bonn, D., ...
Magnetic spins and charges interact strongly in high-temperature superconductors. New physics emerges as layers of copper oxide are tuned towards the boundary of the superconducting phase. As the...
Oxygen Chain Disorder as the Weak Scattering Source in YBa$_2$Cu$_3$O$_{6.50}$ (2006)
Bobowski, J. S., Turner, P. J., Harris, R., Liang, Ruixing, Bonn, D. A., Hardy, W. N.
The microwave conductivity of an ultra-pure single crystal of YBa$_2$Cu$_3$O$_{6.50}$ has been measured deep in the superconducting state as a continuous function of frequency from $0.5\to20$ GHz....
Avoided Quantum Criticality in YBa_2Cu_3O_y and La_{2-x}Sr_xCuO_4 (2006)
Sonier, J. E., Callaghan, F. D., Ando, Y., Kiefl, R. F., Brewer, J. H., Kaiser, C. V., ...
Spin-glass magnetism confined to individual weakly interacting vortices is detected in two different families of high-transition-temperature (T_c) superconductors, but only in samples on the...
Peets, D. C., Mottershead, J. D. F., Wu, B., Elfimov, I. S., Liang, R., Hardy, W. N., ...
Single-particle spectroscopic probes, such as scanning tunneling and angle-resolved photoemission spectroscopy (ARPES), have provided us with crucial insights into the complex electronic structure of...
Yamani, Z., Statt, B. W., MacFarlane, W. A., Liang, Ruixing, Bonn, D. A., Hardy, W. N.
Nuclear magnetic resonance (NMR) measurements of CuO chains of detwinned Ortho-II YBa$_2$Cu$_3$O$_{6.5}$ (YBCO6.5) single crystals reveal unusual and remarkable properties. The chain Cu resonance...
Onset of a boson mode at superconducting critical point of underdoped YBa2Cu3Oy (2006)
Doiron-Leyraud, Nicolas, Sutherland, Mike, Li, S. Y., Taillefer, Louis, Liang, Ruixing, Bonn, D. A., ...
The thermal conductivity $\kappa$ of underdoped \Y was measured in the $T \to 0$ limit as a function of hole concentration $p$ across the superconducting critical point at $p_{SC}$ = 5.0%. ``Time...
Harris, R., Turner, P. J., Kamal, Saeid, Hosseini, A. R., Dosanjh, P., Mullins, G. K., ...
Extensive measurements of the microwave conductivity of highly pure and oxygen-ordered \YBCO single crystals have been performed as a means of exploring the intrinsic charge dynamics of a d-wave...
Insulating transition in the flux-flow resistivity of a high temperature superconductor (2005)
Morgan, Benjamin, Broun, D. M., Liang, Ruixing, Bonn, D. A., Hardy, W. N., Waldram, J. R.
Measurements of the DC resistivity of under-doped cuprate superconductors have revealed a metal--insulator transition at low temperatures when superconductivity is suppressed by a very large magnetic...
Evaluation of CuO2 plane hole doping in YBa2Cu3O6+x single crystals (2005)
Liang, Ruixing, Bonn, D. A., Hardy, W. N.
The electron hole concentration p in the CuO2 planes of YBa2Cu3O6+x (YBCO) has been evaluated using the unit cell length in the c-direction together with a simple estimation for p in the chain oxygen...
Apparatus for high resolution microwave spectroscopy in strong magnetic fields (2005)
Huttema, W. A., Morgan, B., Turner, P. J., Hardy, W. N., Zhou, Xiaoqing, Bonn, D. A., ...
We have developed a low temperature, high-resolution microwave surface impedance probe that is able to operate in high static magnetic fields. Surface impedance is measured by cavity perturbation of...
Superfluid Density in a Highly Underdoped YBCO Superconductor (2005)
Broun, D. M., Huttema, W. A., Turner, P. J., Ozcan, S., Morgan, B., Liang, Ruixing, ...
The superfluid density rho_s(T) = 1/lambda^2(T) has been measured at 2.64 GHz in highly underdoped YBCO, at 37 dopings with T_c between 3 K and 17 K. Within limits set by the transition width Delta...
Sonier, J. E., Callaghan, F. D., Brewer, J. H., Hardy, W. N., Bonn, D. A., Liang, R.
This paper has been withdrawn by the authors, because of results obtained from a more exhaustive study of both YBa_2Cu_3O_y and La_{2-x}Sr_xCuO_4 (see cond-mat/0610051).
The a-axis optical conductivity of detwinned ortho-II YBa_2Cu_3O_6.50 (2005)
Hwang, J., Yang, J., Timusk, T., Sharapov, S. G., Carbotte, J. P., Bonn, D. A., ...
The a-axis optical properties of a detwinned single crystal of YBa_2Cu_3O_6.50 in the ortho II phase (Ortho II Y123, T_c= 59 K) were determined from reflectance data over a wide frequency range (70 -...
Stock, C., Buyers, W. J. L., Yamani, Z., Broholm, C., Tun, Z., ...
We have mapped the neutron scattering spin spectrum at low-energies in YBa2Cu3O6.353 (Tc=18 K) where the doping ~0.06 is near the critical value (pc=0.055) for superconductivity. No coexistence with...
Fermi Surface and Quasiparticle Excitations of overdoped Tl2Ba2CuO6+d by ARPES (2005)
Plate, M., Mottershead, J. D. F., Elfimov, I. S., Peets, D. C., Liang, Ruixing, Bonn, D. A., ...
The electronic structure of the high-T_c superconductor Tl2Ba2CuO6+d is studied by ARPES. For a very overdoped Tc=30K sample, the Fermi surface consists of a single large hole pocket centered at...
Doping dependence of the superconducting gap in Tl_2Ba_2CuO_{6+delta} from heat transport (2005)
Hawthorn, D. G., Li, S. Y., Sutherland, M., Boaknin, Etienne, Hill, R. W., Proust, C., ...
We present low-temperature thermal conductivity measurements on the cuprate Tl_2Ba_2CuO_{6+delta} throughout the overdoped regime. In the T -> 0 limit, the thermal conductivity due to d-wave nodal...
Delocalized fermions in underdoped cuprates (2005)
Sutherland, Mike, Li, S. Y., Hawthorn, D. G., Hill, R. W., Ronning, F., Tanatar, M. A., ...
Low temperature heat transport was used to investigate the ground state of high-purity single crystals of the lightly-doped cuprate YBa$_{2}$Cu$_{3}$O$_{6.33}$. Samples were measured on either side...
Stock, C., Buyers, W. J. L., Cowley, R. A., Clegg, P. S., Coldea, R., Frost, C. D., ...
We have investigated the spin fluctuations at energy transfers up to ~110 meV, well above the resonance energy (33 meV) in the YBa2Cu3O6.5 ortho-II superconductor using neutron time-of-flight and...
Universal scaling relation in high-temperature superconductors (2004)
Homes, C. C., Dordevic, S. V., Strongin, M., Bonn, D. A., Liang, Ruixing, Hardy, W. N., ...
Scaling laws express a systematic and universal simplicity among complex systems in nature. For example, such laws are of enormous significance in biology. Scaling relations are also important in the...
Zooming-in on the charge ordering in YBa2Cu3O6.5 (2004)
Feng, D. L., Rusydi, A., Abbamonte, P., Venema, L., Elfimov, I., Liang, R., ...
We report direct evidence of charge/orbital ordering of low energy electronic states of $Cu$ in YBa$_2$Cu$_3$O$_{6+x}$ ortho-II phase in both the $CuO_3$ chain and the CuO$_2$ plane. Huge enhancement...
Hosseini, A., Broun, D. M., Sheehy, D. E., Davis, T. P., Franz, M., Liang, Ruixing, ...
In the cuprate superconductor $YBa_2Cu_3O_{6+x}$, hole doping in the $CuO_2$ layers is controlled by both oxygen content and the degree of oxygen-ordering. At the composition $\rm YBa_2Cu_3O_{6.35}$,...
Coherence, incoherence and scaling along the c axis of YBa_2Cu_3O_{6+x} (2003)
Homes, C. C., Dordevic, S. V., Bonn, D. A., Liang, R., Hardy, W. N., Timusk, T.
The optical properties of single crystals of YBa_2Cu_3O_{6+x} have been examined along the c axis above and below the critical temperature (T_c) for a wide range of oxygen dopings. The temperature...
Pereg-Barnea, T., Turner, P. J., Harris, R., Mullins, G. K., Bobowski, J. S., Raudsepp, M., ...
Zero-field electron spin resonance (ESR) of dilute Gd ions substituted for Y in the cuprate superconductor YBa$_2$Cu$_3$O$_{\rm 6+y}$ is used as a novel technique for measuring the absolute value of...
Broun, D. M., Turner, P. J., Mullins, G. K., Sheehy, D. E., Zheng, X. G., Kim, S. K., ...
We report microwave surface impedance measurements made on a single crystal of PrOs_4Sb_12 across the frequency range 0.5 to 21 GHz. The penetration depth data provide clear thermodynamic evidence...
Cu NMR Study of Detwinned Single Crystals of Ortho--II YBCO6.5 (2003)
Yamani, Z., MacFarlane, W. A., Statt, B. W., Bonn, D., Liang, R., Hardy, W. N.
Copper NMR has been used as a local probe of the oxygen ordering in Ortho--II YBa2Cu3O6.5 crystals grown in BaZrO3 crucibles. Line assignments have been made to each of the expected...
Diffusion of Nonequilibrium Quasiparticles in a Cuprate Superconductor (2003)
Gedik, N., Orenstein, J., Liang, Ruixing, Bonn, D. A., Hardy, W. N.
We report a transport study of nonequilibrium quasiparticles in a high-Tc cuprate superconductor using the transient grating technique. Low-intensity laser excitation (at photon energy 1.5 eV) was...
Single-quasiparticle stability and quasiparticle-pair decay in YBa2Cu3O6.5 (Ortho II) (2003)
Gedik, N., Blake, P., Spitzer, R. C., Orenstein, J., Liang, Ruixing, Bonn, D. A., ...
We report results and analysis of time-resolved photoinduced reflectivity experiments on the cuprate superconductor YBa2Cu3O6.5. The sample, which has Tc=45 K, was characterized by a high degree of...
Stock, C., Buyers, W. J. L., Liang, R., Peets, D., Tun, Z., Bonn, D., ...
We describe the relation between spin fluctuations and superconductivity in a highly-ordered sample of YBaCu3O6.5 using both polarized and unpolarized neutron inelastic scattering. The spin...
Turner, P. J., Broun, D. M., Kamal, Saeid, Hayden, M. E., Bobowski, J. S., Harris, R., ...
A novel low temperature bolometric method has been devised and implemented for high-precision measurements of the microwave surface resistance of small single-crystal platelet samples having very low...
Transport in Ultraclean YBa$_2$Cu$_3$O$_7$: neither Unitary nor Born Impurity Scattering (2003)
Hill, R. W., Lupien, Christian, Sutherland, M., Boaknin, Etienne, Hawthorn, D. G., Proust, Cyril, ...
The thermal conductivity of ultraclean YBa$_2$Cu$_3$O$_7$ was measured at very low temperature in magnetic fields up to 13 T. The temperature and field dependence of the electronic heat conductivity...
Doping dependence of superconducting gap in YBa_2Cu_3O_y from universal heat transport (2003)
Sutherland, Mike, Hawthorn, D. G., Hill, R. W., Ronning, F., Wakimoto, S., Zhang, H., ...
Thermal transport in the T -> 0 limit was measured as a function of doping in high-quality single crystals of the cuprate superconductor YBa_2Cu_3O_y. The residual linear term kappa_0/T is found to...
Sum rules and energy scales in the high-temperature superconductor YBa2Cu3O6+x (2003)
Homes, C. C., Dordevic, S. V., Bonn, D. A., Liang, Ruixing, Hardy, W. N.
The Ferrell-Glover-Tinkham (FGT) sum rule has been applied to the temperature dependence of the in-plane optical conductivity of optimally-doped YBa_2Cu_3O_{6.95} and underdoped YBa_2Cu_3O_{6.60}....
Sutherland, Mike, Hawthorn, D. G., Hill, R. W., Ronning, F., Wakimoto, S., Zhang, H., ...
Heat transport in the cuprate superconductors YBa$_2$Cu$_3$O$_{y}$ and La$_{2-x}$Sr$_x$CuO$_4$ was measured at low temperatures as a function of doping. A residual linear term kappa_{0}/T is observed...
Doping dependence of superconducting gap in Yba2Cu3Oy from universal heat transport (2003)
Sutherland, M., Hawthorn, D.G., Hill, R.W., Ronning, F., Wakimoto, S., Zhang, H., ...
Hole concentration and phonon renormalization in Ca-doped YBa_2Cu_3O_y (6.76 < y < 7.00) (2002)
Hewitt, K. C., Chen, X. K., Roch, C., Chrzanowski, J., Irwin, J. C., Altendorf, E. H., ...
In order to access the overdoped regime of the YBa_2Cu_3O_y phase diagram, 2% Ca is substituted for Y in YBa_2Cu_3O_y (y = 7.00,6.93,6.88,6.76). Raman scattering studies have been carried out on...
Growth of Orthorhombic Tl-2201 Single Crystals by the Self-Flux Method (2002)
Peets, D. C., Liang, Ruixing, Bonn, D. A., Hardy, W. N., Raudsepp, M.
This article's content has now been absorbed into cond-mat/0609250, which supercedes it.
Top-Seeded Melt-Growth of YBa_2Cu_3O_x Crystals for Neutron Diffraction Studies (2002)
Peets, D. C., Liang, Ruixing, Stock, C., Buyers, W. J. L., Tun, Z., Taillefer, L., ...
We have grown cubic centimetre-size crystals of YBa2Cu3Ox suitable for neutron studies, by a top-seeded melt-growth technique. Growth conditions were optimized with an eye toward maximizing phase...