Ma, C., Zeng, L. J., Yang, H. X., Shi, H. L, Che, R. C., Liang, C. Y., ...
The structural properties of the ROFeM (R=La, Nd; M=As, P) materials have been analyzed by means of electron diffraction, high-resolution transmission-electron microscopy (TEM) and in-situ cooling...
Zeng, L. J., Yang, H. X., Zhang, Y., Tian, H. F., Ma, C., Qin, Y. B., ...
Electric transport measurements of the charge frustrated LuFe2O4, in which the charge ordering (CO) and electronic ferroelectricity are found, reveal strong nonlinear electric conduction upon...
Multi-ferroelectricity in charge ordered LuFe2O4(LuFeO3)n with n=1 (2008)
Yang, H. X., Zhang, Y., Ma, C., Tian, H. F., Qin, Y. B., Zhao, Y. G., ...
Electronic ferroelectricity from charge ordering (CO) is currently a significant issue that has been extensively investigated in the charge/spin frustrated LuFe2O4 system. Chemical substitution and...
Transport properties in Cu$_{x}$TiSe$_{2}$ (0.015$\leq$x$\leq$0.110) Single Crystal (2007)
Wu, G., Yang, H. X., Zhao, L., Luo, X. G., Wu, T., Wang, G. Y., ...
Transport properties are systematically studied for the single crystals Cu$_{x}$TiSe$_{2}$ (0.015$\leq$x$\leq$0.110). Both of in-plane and out-of-plane resistivity show the coexistence of...
Microstructure and charge-ordering transitions in LuFe2O4 (2007)
Zhang, Y., Yang, H. X., Ma, C., Tian, H. F., *, J. Q. Li
Microstructure properties, phase transitions, and charge ordering in the LuFe2O4 materials have been extensively investigated by means of transmission electron microscopy (TEM). The (001) twins as a...
Charge-stripe order in the electronic ferroelectric LuFe2O4 (2007)
Zhang, Y., Yang, H. X., Ma, C., Tian, H. F., *, J. Q. Li
The structural features of the charge ordering states in LuFe2O4 are characterized by in-situ cooling TEM observations from 300K down to 20K. Two distinctive structural modulations, a major q1= (1/3,...
Electronic structure and electron energy-loss spectra of Sr0.35CoO2 (2006)
Xiao, R. J., Yang, H. X., Xu, L. F., Zhang, H. R., Shi, Y. G., Li, J. Q.
The electronic structure of Sr0.35CoO2, structurally analogous to the layered NaxCoO2, has been evaluated using the local spin density approximation (LSDA). We find that evident c-dispersions appear...
Xiao, R. J., Chen, J. H., Yang, H. X., Ma, C., Xu, Q., Zandbergen, H. W., ...
Measurements by high-resolution electron energy-loss spectroscopy (HREELS) of NaxCoO2 reveal spectral features that differ remarkably between the metallic Na0.33CoO2 and the charge-ordered insulator...
Xiao, R. J., Li, K. Q., Yang, H. X., Che, G. C., Zhang, H. R., Ma, C., ...
We performed an extensive investigation on the correlations among superconductivity, structural instability and band filling in Nb1-xB2 materials. Structural measurements reveal that a notable phase...
Xiao, R. J., Yang, H. X., Li, J. Q.
The electronic band structures of the parent compound Na0.3CoO2 and the hydrated superconductor Na0.3CoO2.1.3H2O were evaluated using the local spin density approximation (LSDA). Systematic analysis...
Raman Spectroscopy Study of alpha-, beta-, gamma-NaxCoO2 and gamma-(Ca,Sr)xCoO2 (2006)
Yang, H. X., Xia, Y., Shi, Y. G., Tian, H. F., Xiao, R. J., Liu, X., ...
Raman spectroscopy measurements have been performed on alpha-, beta-, gamma-NaxCoO2 phases differing in their stacking of CoO6 octahedra along the c-axis direction. The results demonstrate that, in...
Shi, Y. G., Yang, H. X., Huang, H., Liu, X., Li, J. Q.
Two series of alpha and beta-NaxCoO2 materials have been prepared by means of Na deintercalation from the parent alpha-NaCoO2 and beta-Na0.6CoO2 phases, respectively. The...
Structural properties and cation ordering in layered hexagonal CaxCoO2 (2005)
Yang, H. X., Shi, Y. G., Liu, X., Xiao, R. J., Tian, H. F., Li, J. Q.
A series of CaxCoO2 (0.15
Yang, H. X., Shi, Y. G., Guo, Y. Q., Liu, X., Xiao, R. J., Luo, J. L., ...
Layered Sr0.35CoO2 has been synthesized by means of an ion exchange reaction from Na0.7CoO2. Resistivity measurements show that this material can be either metallic or semiconducting depending on the...
Effects of Mn and Ti doping on superconductivity and charge ordering in NaxCoO2 system (2005)
Shi, Y. G., Yang, H. X., Liu, X., Ma, W. J., Nie, C. J., Huang, W. W., ...
The superconductivity in Na0.3Co1-xMxO2.1.3H2O and the charge ordering in Na0.5Co1-xMxO2 have been investigated for M = Mn and Ti substituting for Co. We have first successfully synthesized the...
Electron energy loss spectra of Na0.33CoO2.yH2O (y = 0, 0.6 and 1.3) (2004)
Li, J. Q., Yang, H. X., Xiao, R. J., Shi, Y. G., Zhang, H. R
Electron energy loss (EEL) spectra have been obtained on materials with the nominal compositions of Na0.33CoO2_yH2O (y = 0, 0.6 and 1.3). Spectral analyses revealed systematic changes in the low-loss...
Yang, H. X., Nie, C. J., Shi, Y. G., Yu, H. C., Ding, S., Liu, Y. L., ...
The nonstoichiometric NaxCoO2 system exhibits extraordinary physical properties that correlate with temperature and Na concentration in its layered lattice without evident long-range structure...
Yang, H. X., Shi, Y. G., Nie, C. J., Wu, D., Yang, L. X., Dong, C., ...
Transmission electron microscopy observations reveal the presence of complex superstructures and remarkable phase separation in association with Na-ordering phenomenon in y-Na0.5CoO2. Resistivity and...
Off-axis electron holography and microstructure of Ba0.5Sr0.5TiO3 thin film grown on LaAlO3 (2004)
Tian, H. F., Yu, H. C., Zhu, X. H., Wang, Y. G., Zheng, D. N., Yang, H. X., ...
Epitaxial Ba0.5Sr0.5TiO3 thin films grown on the (001) LaAlO3 substrates with the ferroelectric transition of about 250K have been investigated by TEM and off-axis electron holography....
Raman spectroscopy study of NaxCoO2 and superconducting NaxCoO2.yH2O (2004)
Shi, Y. G., Liu, Y. L., Yang, H. X., Nie, C. J., Jin, R., Li, J. Q.
The Raman spectra of the parent compound NaxCoO2 (x=0.75) and the superconducting oxyhydrates NaxCoO2.yH2O with different superconducting temperatures (Tc) have been measured. Five Raman active...
Baryon Spectroscopy at Beijing Electron Positron Collider (2001)
Zou, B. S., Ji, X. B., Yang, H. X., Collaboration, Representing BES
BES Collaboration has collected 58 million $J/\psi$ events at the Beijing Electron-Positron Collider (BEPC). $J/\psi$ decays provide an excellent place for studying excited nucleons and hyperons --...