Zobrazeno 1 - 10
of 675
pro vyhledávání: '"Foo, M."'
We have measured transport properties as a function of temperature and pressure up to 30GPa in the NaxCoO2 system. For the x=0.5 sample the transition temperature at 53K increases with pressure, while paradoxically the sample passes from an insulatin
Externí odkaz:
http://arxiv.org/abs/0710.4341
Autor:
Lee, Minhyea, Viciu, Liliana, Li, Lu, Wang, Yayu, Foo, M. L., Watauchi, S., Pascal Jr., R. A., Cava, R. J., Ong, N. P.
Publikováno v:
Nature Materials 5, 537 (2006).
Research on the oxide perovskites has uncovered electronic properties that are strikingly enhanced compared with those in conventional metals. Examples are the high critical temperatures of the cuprate superconductors and the colossal magnetoresistan
Externí odkaz:
http://arxiv.org/abs/cond-mat/0606426
Publikováno v:
J. Phys. Chem. of Solids 67, 235 (2006)
We report detailed Fermi surface topology and quasiparticle dynamics of the host cobaltate Na0.7CoO2. A direct mapping of the Fermi surface is carried out by angle-resolved photoemission spectroscopy (ARPES). Fermi surface at temperature 16K is a hol
Externí odkaz:
http://arxiv.org/abs/cond-mat/0605289
Autor:
Viciu, L., Bos, J. W. G., Zandbergen, H. W., Huang, Q., Foo, M. L., Ishiwata, S., Ramirez, A. P., Lee, M., Ong, N. P., Cava, R. J.
The crystal structures of the NaxCoO2 phases based on three-layer NaCoO2, with x=0.32, x=0.51, x=0.60, x=0.75 and x=0.92, determined by powder neutron diffraction, are reported. The structures have triangular CoO2 layers interleaved by sodium ions, a
Externí odkaz:
http://arxiv.org/abs/cond-mat/0601587
The structure of Na0.5CoO2, the low temperature insulator that separates the magnetic and superconducting regions in the NaxCoO2.yH2O phase diagram, is studied by high resolution powder neutron diffraction at temperatures between 10 and 300 K. Profil
Externí odkaz:
http://arxiv.org/abs/cond-mat/0601131
The specific heats of three samples of Na0.35CoO2,1.3H2O show an evolution of the superconductivity, and its ultimate disappearance, with increasing sample age. An overall increase in pair-breaking action, which occurs preferentially in an electron b
Externí odkaz:
http://arxiv.org/abs/cond-mat/0503690
Autor:
Hasan, M. Z., Qian, D., Li, Y., Fedorov, A. V., Chuang, Y. -D., Kuprin, A. P., Foo, M. L., Cava, R. J.
Publikováno v:
Annals of Physics 321 (7): 1568-1574 (2006)
Recently discovered class of cobaltate superconductors (Na0.3CoO2.nH2O) is a novel realization of interacting quantum electron systems in a triangular network with low-energy degrees of freedom. We employ angle-resolved photoemission spectroscopy to
Externí odkaz:
http://arxiv.org/abs/cond-mat/0501530
Publikováno v:
Material Research Bulletin vol. 40/4 (2005), p. 665-670
The hydration phase diagram for sodium cobalt oxyhydrate, Na0.3CoO2*yH2O (y=0, 0.6, 1.3), was determined as a function of relative humidity at 298K. It is found that greater than 75% relative humidity is needed for complete hydration of anhydrous Na0
Externí odkaz:
http://arxiv.org/abs/cond-mat/0411387
The superconducting-state heat capacity of Na$_{0.3}$CoO$_{2}$$\cdot$1.3H$_{2}$O shows unusual, marked deviations from BCS theory, at all temperatures. At low temperatures the heat capacity has the $T^2$ dependence characteristic of line nodes in the
Externí odkaz:
http://arxiv.org/abs/cond-mat/0409760
Autor:
Huang, Q., Foo, M. L., Pascal Jr., R. A., Lynn, J. W., Toby, B. H., He, Tao, Zandbergen, H. W., Cava, R. J.
The determination by powder neutron diffraction of the ambient temperature crystal structures of compounds in the NaxCoO2 family, for 0.3 < x <= 1.0, is reported. The structures consist of triangular CoO2 layers with Na ions distributed in intervenin
Externí odkaz:
http://arxiv.org/abs/cond-mat/0406570