Lattice distortion and magnetic quantum phase transition in CeFeAs(1-x)P(x)O (2009)
De La Cruz, Clarina, Hu, W. Z., Li, Shiliang, Huang, Q., Lynn, J. W., Green, M. A., ...
We use neutron scattering to show that replacing the larger arsenic with smaller phosphorus in CeFeAs(1-x)P(x)O simultaneously suppresses the AF order and orthorhombic distortion near x = 0.4,...
Optical study on the spin-density wave properties in single crystalline Na$_{1-\delta}$FeAs (2009)
Hu, W. Z., Li, G., Zheng, P., Chen, G. F., Luo, J. L., Wang, N. L.
We report an optical investigation on the in-plane charge dynamics for Na$_{1-\delta}$FeAs single crystal. A clear optical evidence for the spin-density wave (SDW) gap is observed. As the...
Chen, Z. G., Xu, G., Hu, W. Z., Zhang, X. D., Zheng, P., Chen, G. F., ...
BaNi$_2$As$_2$ exhibits a first order structural transition at 130 K. Understanding this structural transition is a crucial step towards understanding the electronic properties of the material. We...
Multiple phase transitions in single-crystalline Na$_{1-\delta}$FeAs (2009)
Chen, G. F., Hu, W. Z., Luo, J. L., Wang, N. L.
Specific heat, resistivity, susceptibility, Hall coefficient and optical measurements were performed on the high quality single crystalline Na$_{1-\delta}$FeAs. This compound is found to undergo...
Optical and Raman spectroscopy studies on Fe-based superconductors (2009)
Hu, W. Z., Zhang, Q. M., Wang, N. L.
A brief review of optical and Raman studies on the Fe-based superconductors is given, with special emphasis on the competing phenomenon in this system. Optical investigations on ReFeAsO...
Chen, G. F., Chen, Z. G., Dong, J., Hu, W. Z., Li, G., Zhang, X. D., ...
We report on a comprehensive study of the transport, specific heat, magnetic susceptibility and optical spectroscopy on single crystal of Fe$_{1.05}$Te. We confirm that Fe$_{1.05}$Te undergoes a...
Goko, T., Aczel, A. A., Baggio-Saitovitch, E., Bud'ko, S. L., Canfield, P. C., Carlo, J. P., ...
The recent discovery and subsequent developments of FeAs-based superconductors have presented novel challenges and opportunities in the quest for superconducting mechanisms in correlated-electron...
Evidence for the band broadening across the ferromagnetic transition in Cr$_{1/3}$NbSe$_2$ (2008)
Hu, W. Z., Wang, G. T., Hu, Rongwei, Petrovic, C., Morosan, E., ...
The electronic structure of Cr$_{1/3}$NbSe$_2$ is studied via optical spectroscopy. We observe two low-energy interband transitions in the paramagnetic phase, which split into four peaks as the...
Aczel, A. A., Baggio-Saitovitch, E., Budko, S. L., Canfield, P. C., Carlo, J. P., Chen, G. F., ...
Zero-field (ZF) muon spin relaxation ($\mu$SR) measurements have revealed static commensurate magnetic order of Fe moments in NdOFeAs below $T_{N} \sim 135$ K, with the ordered moment size nearly...
Li, G., Hu, W. Z., Dong, J., Li, Z., Zheng, P., Chen, G. F., ...
We performed optical spectroscopy measurement on a superconducting Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$ single crystal with T$_c$=37 K. Formation of the superconducting energy gaps in the far-infared...
Chen, G. F., Li, Z., Dong, J., Li, G., Hu, W. Z., Zhang, X. D., ...
We have successfully grown high quality single crystals of SrFe$_2$As$_2$ and A$_{0.6}$K$_{0.4}$Fe$_2$As$_2$(A=Sr, Ba) using flux method. The resistivity, specific heat and Hall coefficient have been...
Hu, W. Z., Dong, J., Li, G., Li, Z., Zheng, P., Chen, G. F., ...
We performed optical spectroscopy measurement on single crystals of BaFe$_2$As$_2$ and SrFe$_2$As$_2$, the parent compounds of FeAs based superconductors. Both are found to be quite metallic with...
Superconductivity in hole-doped (Sr$_{1-x}$K$_x$)Fe$_2$As$_2$ (2008)
Chen, G. F., Li, Z., Li, G., Hu, W. Z., Dong, J., Zhang, X. D., ...
A series of layered (Sr$_{1-x}$K$_x$)Fe$_2$As$_2$ compounds with nominal x=0 to 0.40 are synthesized by solid state reaction method. Similar to other parent compounds of iron-based pnictide...
Carlo, J. P., Uemura, Y. J., Goko, T., MacDougall, G. J., Rodriguez, J. A., Yu, W., ...
Muon spin relaxation (MuSR) measurements in iron oxy-pnictide systems have revealed: (1) commensurate long-range order in undoped LaOFeAs; (2) Bessel function line shape in La(O0.97F0.03)FeAs which...
Chen, G. F., Li, Z., Wu, D., Dong, J., Li, G., Hu, W. Z., ...
Different element substitution effects in transition metal oxypnictide Re(O$_{1-x}$F$_x$)TAs with Re=La, Ce, Nd, Eu, Gd, Tm, T=Fe, Ni, Ru, were studied. Similar to the La- or Ce-based systems, we...
Chen, G. F., Li, Z., Wu, D., Li, G., Hu, W. Z., Dong, J., ...
A series of layered CeO$_{1-x}$F$_x$FeAs compounds with x=0 to 0.20 are synthesized by solid state reaction method. Similar to the LaOFeAs, the pure CeOFeAs shows a strong resistivity anomaly near...
Competing Orders and Spin-Density-Wave Instability in La(O$_{1-x}$F$_x$)FeAs (2008)
Dong, J., Zhang, H. J., Xu, G., Li, Z., Li, G., Hu, W. Z., ...
The interplay between different ordered phases, such as superconducting, charge or spin ordered phases, is of central interest in condensed matter physics. The very recent discovery of...
Strong-coupling superconductivity in layered nickel-based LaO$_{1-x}$F$_x$NiAs (2008)
Li, Z., Chen, G. F., Dong, J., Li, G., Hu, W. Z., Wu, D., ...
A series of layered nickel-based LaO$_{1-x}$F$_x$NiAs compounds with x=0 to 0.15 are synthesized by solid state reactions. The pure LaONiAs exhibits bulk superconductivity with Tc $\sim$ 2.75 K....
Superconducting properties of Fe-based layered superconductor LaO$_{0.9}$F$_{0.1-\delta}$FeAs (2008)
Chen, G. F., Li, Z., Li, G., Zhou, J., Wu, D., Dong, J., ...
We have employed a new route to synthesize single phase F-doped LaOFeAs compound and confirmed the superconductivity above 20 K in this Fe-based system. We show that the new superconductor has a...
Anomalous metallic state of Cu$_{0.07}$TiSe$_2$: an optical spectroscopy study (2007)
Li, G., Hu, W. Z., Dong, J., Qian, D., Hsieh, D., Hasan, M. Z., ...
We report an optical spectroscopy study on the newly discovered superconductor Cu$_{0.07}$TiSe$_2$. Consistent with the development from a semimetal or semiconductor with a very small indirect energy...
Semimetal to semimetal charge density wave transition in 1T-TiSe$_2$ (2007)
Li, G., Hu, W. Z., Qian, D., Hsieh, D., Hasan, M. Z., Morosan, E., ...
We report an infrared study on 1$T$-TiSe$_2$, the parent compound of the newly discovered superconductor Cu$_x$TiSe$_2$. Previous studies of this compound have not conclusively resolved whether it is...
Optical study of the charge-density-wave mechanism in 2$H$-TaS$_2$ and Na$_x$TaS$_2$ (2007)
Hu, W. Z., Li, G., Yan, J., Wen, H. H., Wu, G., Chen, X. H., ...
We report an optical study of transition metal dichalcogenide 2$H$-TaS$_2$ and Na intercalated superconductor Na$_x$TaS$_2$ over a broad frequency range at various temperatures. A clear gap feature...
Phonon softening in HgBa§2CuO§4§+§#d and MgB§2. (2006)
Uchiyama, H., Baron, A.Q.R., Tsutsui, S., Tanaka, Y., Ishikawa, D., Lee, S., ...
Journal of Physics and Chemistry of Solids, 67(2006) S.294-97
Phonon softening in HgBa§2CuO§4§+§#d and MgB§2. (2006)
Uchiyama, H., Baron, A.Q.R., Tsutsui, S., Tanaka, Y., Ishikawa, D., Lee, S., ...
Journal of Physics and Chemistry of Solids, 67(2006) S.294-97
Phonon softening in HgBa§2CuO§4§+§#d and MgB§2. (2004)
Uchiyama, H., Baron, A.Q.R., Tsutsui, S., Tanaka, Y., Ishikawa, D., Lee, S., ...
7th Internat.Conf.on Spectroscopies in Novel Superconductors (SNS 2004), Sitges, E, July 11-16, 2004