High-pressure synthesis and superconducting properties of the oxychloride superconductor (Sr,Ca)(3)Cu2O4+delta Cl2-y
High-pressure synthesis and superconducting properties of the oxychloride superconductor (Sr,Ca)(3)Cu2O4+delta Cl2-y
复制标题
氯氧化物超导体(Sr,Ca)(3)Cu2O4 delta Cl2-y的高压合成及超导性能
DOI：
10.1103/physrevb.61.778
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发表时间：
2000
影响因子：
3.7
通讯作者：
S. Tanaka
中科院分区：
文献类型：
--
作者：
C. Jin;R. Puźniak;Z. Zhao;X.J. Wu;T. Tatsuski;T. Tamura;S. Adachi;K. Tanabe;H. Yamauchi;S. Tanaka
在5.0 Ga和1000 ℃附近合成了含氯的（Sr，Ca）（3）Cu_2 O_4 + δ Cl_2-y超导体。该双层[CuO 2]化合物结晶为（La，Sr）（2）CaCu 2 O 6结构，Cl位于[CuO 2]面的顶端阴离子位。这些超导体的临界转变温度T-c达到80 K。研究了Sr_（2.3）Ca_（0.7）Cu_2 O_（4+）δ Cl_（1.3）超导体的不可逆场H_i和晶内临界电流密度I_i。发现超导体的不可逆性场可用幂律关系（I-T/T-c）（n）来描述，其中n近似等于2。在H-T面上，还原的H-irr（T/T-c）线位于YBa_2Cu_3 O_7和Bi_2Sr_2CaCu_2 O_8的H-irr（T/T-c）线之间，靠近HgBa_2CaCu_2 O_6 + δ。临界电流密度J（c）（T）是从Bean临界状态模型中提取的，并显示出平滑的温度依赖性。（Sr，Ca）（3）Cu_2 O_4 + deltaCl_2-y的H_（irr）（T）和J_（c）（T）的一般行为与氧化物高T_c超导铜酸盐（HTSC）的H_（irr）（T）和J_（c）（T）无显著差异。离面间距仍然是评价卤氧化物高温超导体层间耦合的重要参数，这与氧化物高温超导体是一致的。研究结果表明，即使用卤氧化物代替常规的氧化物，卤氧化物超导体仍具有潜在的应用前景。
Chlorine-containing (Sr,Ca)(3)CU2O4+deltaCl2-y superconductors have been synthesized at 5.0 Ga and similar to 1000 degrees C. The double-[CuO2] layered compound crystallizes into (La,Sr)(2)CaCu2O6 structure with Cl residing at the apical anion site relative to the [CuO2] plane. The critical transition temperature T-c 80K has been achieved in these superconductors. The Sr2.3Ca0.7Cu2O4+deltaCl1.3 superconductor was studied in terms of irreversibility field Hi, and intragrain critical current density I,. It is found that the irreversibility field of the superconductor can be described by the power law dependence (I-T/T-c)(n), with n similar to 2. The reduced H-irr(T/T-c) line is positioned between those of YBa2Cu3O7 and Bi2Sr2CaCu2O8 in the H-T plane, close to HgBa2CaCu2O6+delta. The critical current density J(c)(T) was extracted from the Bean critical-state model and showed a smooth temperature dependence. No significant difference was found for the general behavior of H-irr(T) and J(c)(T) of (Sr,Ca)(3)Cu2O4+deltaCl2-y from those of oxide high-T-c superconducting cuprates (HTSC). The off-plane space remains the important parameter to evaluate interlayer coupling of the oxyhalide HTSC, which is consistent with oxide HTSC. The results suggest the potential application capability of the oxyhalide superconductors even though the off-plane block is composed of oxyhalide instead of the routine oxides.