本文通过固相反应法制备了(Y1-xCax)Ba2Cu3O7-δ (x=0,0.06,0.12)多晶样品并在流动氧气下退火,研究了Ca掺杂对超导体CuO2面空穴浓度的影响.热重分析结果显示,相同退火条件下Ca2+/Y3+替代所引入的空穴不会被氧含量的降低所完全补偿.热电势测量数据显示,低温退火就可使未掺杂样品处于“临界掺杂浓度”,而低剂量Ca掺杂则有可能降低CuO2面的空穴浓度.观察发现无论是否掺Ca样品的p(δ)函数都呈非线性关系,可能来源于CuO1-δ链的有序性.计算显示Ca2+/y3+替代可能降低材料的超导性能.
参考文献
| [1] | Loram JW.;Cooper JR.;Talloon JL.;Mirza KA. .Specific heat evidence on the normal state pseudogap[J].The journal of physics and chemistry of solids,1998(10/12):2091-2094. |
| [2] | Tallon JL.;Loram JW.;Williams GVM. .NMR studies on HTS cuprates: Re-assessing the models[J].The journal of physics and chemistry of solids,1998(10/12):2145-2149. |
| [3] | Nazarova EK;Zaleski AJ;Zahariev AL;Stoyanova-lvanova AK;Zalamova KN .Effects of substituting calcium for yttrium on the superconducting properties of YBa2Cu3Oz bulk samples[J].Physica, C. Superconductivity and its applications,2004(4):283-289. |
| [4] | Bernhard C.;Tallon JL. .THERMOELECTRIC POWER OF Y1-XCAXBA2CU3O7-DELTA - CONTRIBUTIONS FROM CUO2 PLANES AND CUO CHAINS[J].Physical Review.B.Condensed Matter,1996(14):10201-10209. |
| [5] | Naqib SH;Semwal A .Low-temperature critical current of Y1-xCaxBa2Cu3O7-delta thin films as a function of hole content and oxygen deficiency[J].Physica, C. Superconductivity and its applications,2005(1/2):14-20. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%