|
|
|
Journal of the Korean Ceramic Society 1998;35(10): 1007. |
| Bi$_2$Sr$_2$Ca$_{1-x}$Na$_x$Cu$_2$O$_{8+y}$ 산화물 고온초전도체의 Ca 위치에 Na 치환 효과 |
| 이민수, 송승용, 이종용, 송기영, 최봉수 |
| 한남대학교 이과대학 물리학과 |
| Effect of Na Substitution for the Ca Site in the Bi$_2$Sr$_2$Ca$_{1-x}$Na$_x$Cu$_2$O$_{8+y}$ Superconductors |
|
|
|
|
|
|
|
| ABSTRACT |
|
The samples of Bi2Sr2Ca1-xNaxCu2O8+y with various carrier concentration were synthesized by substituting Na for Ca ion. The superconducting properties hall coefficients and X-ray powder diffraction were measur-ed the sampled. Single phase samples were obtained for 0$leq$x<0.3 of Bi2Sr2Ca1-xNaxCu2O8+y In the single phase the critical temperature. {{{{ { T}_{c } }} and carrier concentration increase with the increase of Na concentration pass through a maximum and then decreases. In the range of x$geq$0.7 to the Na doped samples however we observed the metal-semiconductor transition. The c-axis seemed to decrease and a and b-axes increase with increasing Na concentration in the single phase. Decreasing of c-axis while increasing x is due to the smaller size of {{{{ {Na}^{+1 } }} ions to the {{{{ { Ca}^{+2 } }} ions. In the range of x>0.3 however the trend becomes ambiguous due to the inclusion of the 10K phase and impurity phase. |
| Key words:
High - T$_c$superconductor, Na subsitution, Hole concentration |
|
|
|
PDF Links
Full text via DOI 
Download Citation 
