Zobrazeno 1 - 10
of 1 481
pro vyhledávání: '"Koshizuka, N."'
Autor:
Machi, T., Kato, I., Hareyama, R., Watanabe, N., Itoh, Y., Koshizuka, N., Arai, S., Murakami, M.
Publikováno v:
Physica C 388-389 (2003) 233
The effects of nonmagnetic Zn and magnetic Ni substitution for Cu site on magnetism are studied by measurements of uniform magnetic susceptibility for lightly doped La_{2-x}Sr_xCu_{1-z}M_zO_4 (M=Zn or Ni) polycrystalline samples. For the parent x=0,
Externí odkaz:
http://arxiv.org/abs/cond-mat/0304482
Autor:
Zhao, Y., Rui, X. F., Cheng, C. H., Zhang, H., Munroe, P., Zeng, H. M., Koshizuka, N., Murakami, M.
MgB2-diamond nanocomposite superconductors have been synthesized by addition of nano-diamond powder. Microstructural analysis shows that the nanocomposite superconductor consists of tightly-packed MgB2 nano-grains (~50-100 nm) with highly-dispersed a
Externí odkaz:
http://arxiv.org/abs/cond-mat/0302365
Autor:
Cheng, C. H., Zhang, H., Zhao, Y., Feng, Y., Rui, X. F., Munroe, P., Zeng, H. M., Koshizuka, N., Murakami, M.
Doping effect of diamond nanoparticles on the superconducting properties of MgB2 bulk material has been studied. It is found that the superconducting transition temperature Tc of MgB2 is suppressed by the diamond-doping, however, the irreversibility
Externí odkaz:
http://arxiv.org/abs/cond-mat/0302202
Publikováno v:
Phys. Rev. B 67, 064516 (2003)
We studied local electronic states near Zn in optimally doped YBa$_2$(Cu$_{1-x}$Zn_x)$_3$O$_{7-\delta}$ and underdoped YBa$_2$(Cu$_{1-x}$Zn_x)$_4$O$_8$ via satellite signals of plane-site Cu(2) nuclear quadrupole resonance (NQR) spectra. From the rel
Externí odkaz:
http://arxiv.org/abs/cond-mat/0301432
Publikováno v:
Phys. Rev. B 66 (2002) 134511
We report Cu nuclear quadrupole resonance experiment on magnetic impurity Ni-substituted YBa$_2$Cu$_{3-x}$Ni$_x$O$_{7-\delta}$. The distribution of Ni-substituted sites and its effect on the Cu electron spin dynamics are investigated. Two samples wit
Externí odkaz:
http://arxiv.org/abs/cond-mat/0206199
Autor:
Eltsev, Yu., Nakao, K., Lee, S., Masui, T., Chikumoto, N., Tajima, S., Koshizuka, N., Murakami, M.
Publikováno v:
Phys. Rev. B 66, 180504(R) (2002)
We report resistivity and the Hall effect measurements in the normal and superconducting states of MgB2 single crystal. The resistivity has been found to be anisotropic with slightly temperature dependent resistivity ratio of about 3.5. The Hall cons
Externí odkaz:
http://arxiv.org/abs/cond-mat/0204027
Publikováno v:
Physica C, v.378-381, 61(2002)
In-plane electrical transport properties of MgB2 single crystals grown under high pressure of 4-6 GPa and temperature of 1400-1700oC in Mg-B-N system have been measured. For all specimens we found sharp superconducting transition around 38.1-38.3K wi
Externí odkaz:
http://arxiv.org/abs/cond-mat/0202133
Publikováno v:
Phys. Rev B65, 140501(R), 2002
We report on study of the electronic anisotropy of the newly discovered MgB2 superconductor using the in-plane resistivity measurements in magnetic field applied perpendicular and parallel to Mg and B planes of MgB2 single crystals. The results show
Externí odkaz:
http://arxiv.org/abs/cond-mat/0201451
Publikováno v:
Physica C 378-381 (2002) 203
We estimated the spread of the magnetically enhanced regions (wipeout regions) around Zn ions in high-Tc superconductors YBa2(Cu1-xZnx)4O8 (x=0, 0.005, 0.01, and 0.022) at T=4.2 K, via the planar 63Cu nuclear spin-lattice relaxation study with Cu nuc
Externí odkaz:
http://arxiv.org/abs/cond-mat/0110548