Interplay of inequivalent atomic positions in resonant x-ray diffraction of Fe3BO6 (2009)
Beutier, G, Ovchinnikova, E, Collins, S P, Dmitrienko, V E, Lorenzo, J E, Hodeau, J-L, ...
'Forbidden' Bragg reflections of iron orthoborate Fe3BO6 were studied theoretically and experimentally in the vicinity of the iron K edge. Their energy spectra are explained as resulting from the...
Direct observation of the high magnetic field effect on the Jahn-Teller state in TbVO4 (2008)
Duc, F, Kazei, Z. A, Frings, P, Bras, W, ...
We report the first direct observation of the influence of high magnetic fields on the Jahn-Teller (JT) transition in TbVO4. Contrary to spectroscopic and magnetic methods, x-ray diffraction directly...
Direct observation of the high magnetic field effect on the Jahn-Teller state in TbVO4 (2007)
Detlefs, C., Duc, F., Kazei, Z. A., Vanacken, J., Frings, P., Bras, W., ...
We report the first direct observation of the influence of high magnetic fields on the Jahn-Teller (JT) transition in TbVO4. Contrary to spectroscopic and magnetic methods, X-ray diffraction directly...
The Fincher-Burke spin excitations and omega/T scaling in the insulating 5% Sr-doped La2CuO4 (2007)
Bao, Wei, Chen, Ying, Yamada, K., Savici, A. T., Russo, P. L., Lorenzo, J. E., ...
Insulating La1.95Sr0.05CuO4 shares with superconducting cuprates the same Fincher-Burke-like spin excitations, which usually are observed in itinerant antiferromagnets. The local spectral function...
Comment on "Two Dimensional Ordering and Fluctuations in alpha'-NaV2O5" (2006)
We claim that the analysis presented by Gaulin et al. (Phys. Rev. Lett. 84, 3446 (2000)) does not prove the two-dimensional character of the transition in NaV2O5 nor the charge ordering mechanism of...
Resonant X-ray diffraction studies on the charge ordering in magnetite (2006)
Nazarenko, E., Lorenzo, J. E., Joly, Y., Hodeau, J. L., Mannix, D., Marin, C.
Here we show that the low temperature phase of magnetite is associated with an effective, although fractional, ordering of the charge. Evidence and a quantitative evaluation of the atomic charges are...
Dynamical spin chirality and spin anisotropy in gapped S=1/2 quantum systems (2006)
Lorenzo, J. E., Boullier, C., Regnault, L. P., Ammerahl, U., Revcolevschi, A.
We have studied the spin anisotropy in spin-singlet ground state compounds and the magnetic chirality, as measured by inelastic polarized neutron scattering techniques, in the chain-sublattice of...
Slow spin-glass and fast spin-liquid components in quasi-two-dimensional La2(Cu,Li)O4 (2005)
Chen, Y., Bao, Wei, Qiu, Y., Lorenzo, J. E., Sarrao, J. L., Ho, D. L., ...
In conventional spin glasses, magnetic interaction is not strongly anisotropic and the entire spin system is believed to be frozen below the spin-glass transition temperature. In La2Cu0.94Li0.06O4,...
Partial spin freezing in the quasi-two-dimensional La2(Cu,Li)O4 (2005)
Chen, Y., Bao, Wei, Qiu, Y., Lorenzo, J. E., Sarrao, J. L., Ho, D. L., ...
In conventional spin glasses, the magnetic interaction is not strongly anisotropic and the entire spin system freezes at low temperature. In La2(Cu,Li)O4, for which the in-plane exchange interaction...
Resonant x-ray scattering experiments on electronic orderings in NdNiO3 single crystals (2005)
Lorenzo, J. E., Hodeau, J. L., Paolasini, L., Lefloch, S., Alonso, J. A., Demazeau, Gérard
We have carried out resonant x-ray scattering experiments on NdNiO3 single crystals aiming at the observation of a predicted orbital ordering that may explain the presence of an antiferromagnetic...
Magnetic structure of the spin-1/2 layer compound NaNiO2 (2005)
Darie, C., Bordet, P., De Brion, S., Holzapfel, M., Isnard, O., Lecchi, A., ...
Anomalous critical behavior near the quantum critical point of a hole-doped La2CuO4 (2004)
Chen, Y., Bao, Wei, Lorenzo, J. E., Stunault, A., Sarrao, J. L., Park, S., ...
The Landau-Ginzburg-Wilson paradigm for critical phenomena is spectacularly successful whenever the critical temperature is finite and all fluctuation modes, with characteristic energies much smaller...
Direct and quantitative determination of the orbital ordering in CeB6 by x-ray diffraction (2004)
Tanaka, Y, Staub, U, Katsumata, K, Lovesey, S W, Lorenzo, J E, Narumi, Y, ...
Lorenzo, J. E., Katsumata, K., Narumi, Y., Shimomura, S., Tanaka, Y., Hagiwara, M., ...
We report the observation of a jump in the a- and c-lattice constants at the critical field H-c1 and at temperatures of the order 40 mK in the S=1/2 spin-gapped compound Cu-2(C5H12N2)(2)Cl-4 by means...
Chasing ghosts in reciprocal space - a novel inelastic neutron multiple scattering process (2004)
Ronnow, H. M., Regnault, L. P., Lorenzo, J. E.
We have discovered that a recently reported weak excitation branch in the spin-Peierls material CuGeO3 is in fact a ghost image of the primary magnetic excitation shifted in reciprocal space by a...
Inelastic neutron polarization analysis in low-dimensional systems (2004)
Regnault, L. P., Ronnow, H. M., Boullier, C., Lorenzo, J. E., Marin, C.
We will review recent results obtained by longitudinal polarization analysis and spherical neutron polarimetry (SNP) on typical low-dimensional strongly correlated electronic systems (spin-Peierls...
Longitudinal-neutron-polarization-analysis study of the spin dynamics in Sr14Cu24O41 (2004)
Boullier, C., Regnault, L. P., Lorenzo, J. E., Ronnow, H. M., Ammerahl, U., Dhalenne, G., ...
The crystallographic structure of the cuprate Sr14Cu24O41 is a misfit stacking of layers of two distinct quantum-spin systems: linear edge-sharing CuO2 chains and 2-leg Cu2O3 spin-ladders....
Charge ordering in oxides : a conundrum solved by resonant diffraction (2003)
Joly, Y., Grenier, S., Lorenzo, J. E.
We show that in mixed-valence 3d transition metal oxides undergoing a structural transition, the low temperature phase results from an effective ordering of the charge. This arrangement and the...
Inelastic neutron polarization analysis (2003)
Regnault, L. P., Ronnow, H. M., Lorenzo, J. E., Bellissent, R., Tasset, F.
We will review recent results obtained by longitudinal polarization analysis (LPA) and spherical neutron polarimetry (SNP) on typical "low-dimensional" strongly correlated electronic systems...
Rideau,D., Monceau,P., Currat,R., Requardt,H., Nad,F., Lorenzo,J. E., ...
Rideau,D., Monceau,P., Currat,R., Requardt,H., Nad,F., Lorenzo,J. E., ...
X-ray anomalous scattering investigations on the charge order in $\alpha^\prime$-NaV$_2$O$_5$ (2001)
Grenier, S., Toader, A., Lorenzo, J. E., Joly, Y., Grenier, B., Ravy, S., ...
Anomalous x-ray diffraction studies show that the charge ordering in $\alpha^\prime$-NaV$_2$O$_5$ is of zig-zag type in all vanadium ladders. We have found that there are two models of the stacking...
Rideau,D., Monceau,P., Currat,R., Requardt,H., Nad,F., Lorenzo,J. E., ...
Comment on "X-Ray Anomalous Scattering Study of a Charge-Ordered State in NaV2O5" (2001)
Bos, S., Grenier, S., Lorenzo, J. E., Ravy, S., Renevier, H.
Charge Ordering and Spin Dynamics in NaV2O5 (2001)
Cepas, O., Grenier, B., Lorenzo, J. E., Regnault, L. P., Ziman, T.
Rideau, D., Monceau, P., Currat, R., Requardt, H., Nad, F., Lorenzo, J. E., ...
Using high-resolution X-ray scattering techniques, we measure the variation, q(x), of the position in reciprocal space of the CDW satellite, in the sliding state, along the length of NbSe_3 whiskers....
Charge Ordering and Spin Dynamics in NaV2O5 (2000)
Grenier, B., Cepas, O., Regnault, L. P., Lorenzo, J. E., Ziman, T., Boucher, J. P., ...
We report high-resolution neutron inelastic scattering experiments on the spin excitations of NaV2O5. Below Tc, two branches associated with distinct energy gaps are identified. From the dispersion...
Comment on "Two Dimensional Ordering and Fluctuations in alpha'-NaV2O5" (2000)
We claim that the analysis presented by Gaulin et al. (Phys. Rev. Lett. 84, 3446 (2000)) does not prove the two-dimensional character of the transition in NaV2O5 nor the charge ordering mechanism of...
Phase slippage at the interface: normal metal/sliding charge-density wave (2000)
Rideau,D., Monceau,P., Requardt,H., Currat,R., Nad,F., Lorenzo,J. E., ...
Phase slippage at the interface: normal metal/sliding charge-density wave (2000)
Rideau, D., Monceau, P., Requardt, H., Currat, R., Nad, F., Lorenzo, J. E., ...
Observation of a Kosterlitz-Thouless state in the spin-Peierls phase transition in CuGeO3 (1999)
Lorenzo, J E, Regnault, L P, Langridge, S, Vettier, C, Sutter, C, Grubel, G, ...
Regnault, L. P., Boucher, J. P., Moudden, H., Lorenzo, J. E., Hiess, A., Ammerahl, U., ...
Below about 150 K, the spin arrangement in the chain arrays of Sr14Cu24O41 is shown to develop in two dimensions (2D). Both the correlations and the dispersion of the observed elementary excitations...
Double gap and solitonic excitations in the spin-Peierls chain CuGeO3 (1998)
Ain, M., Lorenzo, J. E., Regnault, L. P., Dhalenne, G., Revcolevschi, A., Hennion, B., ...
We have studied magnetic excitations in the dimerized spin-Peierls phase of CuGeO3, by high resolution inelastic neutron scattering. We measured the well-defined spin triplet dispersive mode which is...