Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtai...Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtained by Talantsev (2019) in an approach based on an ingenious mix of the Ginzberg-Landau (GL), the Werthamer, Helfand and Hohenberg (WHH), and the Gor’kov, etc., theories which have individually been employed for the same purpose for a long time. Up to the lowest temperature (TL) in each of these data-sets, similarly accurate fits have also been obtained by Malik and Varma (2023) in a radically different approach based on the Bethe-Salpeter equation (BSE) supplemented by the Matsubara and the Landau quantization prescriptions. For T TL, however, while the (GL, WHH, etc.)-based approach leads to Hc2(0) ≈ 100 T, the BSE-based approach leads to about twice this value even at 1 K. In this paper, a fit to one of the said data-sets is obtained for the first time via a thermodynamic approach which, up to TL, is as good as those obtained via the earlier approaches. While this is interesting per se, another significant result of this paper is that for T TL it corroborates the result of the BSE-based approach.展开更多
采用溶胶-凝胶法制备Y0.06Sr0.94Ti1-xFexO3-δ(x为原子分数。x=0.2,0.3,0.4,0.5)混合导体材料,用X射线衍射(XRD)分析该材料的物相,采用交流阻抗法和电子阻塞电极法分别测定其总电导率与离子电导率,研究铁含量对Y0.06Sr0.94T...采用溶胶-凝胶法制备Y0.06Sr0.94Ti1-xFexO3-δ(x为原子分数。x=0.2,0.3,0.4,0.5)混合导体材料,用X射线衍射(XRD)分析该材料的物相,采用交流阻抗法和电子阻塞电极法分别测定其总电导率与离子电导率,研究铁含量对Y0.06Sr0.94TiO3混合导体材料的结构及电性能的影响。结果表明该材料属于单一立方相钙钛矿结构;在测试温度范围内,Y0.06Sr0.94Ti1-xFexO3-δ的总电导率和离子电导率都随温度升高而增大;随 Fe 掺杂量增加,总电导率和离子电导率都增大。在800℃下Y0.06Sr0.94Ti1-xFexO3-δ(x=0.2,0.3,0.4,0.5)的总电导率为0.019~0.12 S/cm,离子电导率为0.0106~0.0153 S/cm。根据传导活化能可以看出,x从0.3增加到0.4时材料的传导机制发生改变。展开更多
文摘Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtained by Talantsev (2019) in an approach based on an ingenious mix of the Ginzberg-Landau (GL), the Werthamer, Helfand and Hohenberg (WHH), and the Gor’kov, etc., theories which have individually been employed for the same purpose for a long time. Up to the lowest temperature (TL) in each of these data-sets, similarly accurate fits have also been obtained by Malik and Varma (2023) in a radically different approach based on the Bethe-Salpeter equation (BSE) supplemented by the Matsubara and the Landau quantization prescriptions. For T TL, however, while the (GL, WHH, etc.)-based approach leads to Hc2(0) ≈ 100 T, the BSE-based approach leads to about twice this value even at 1 K. In this paper, a fit to one of the said data-sets is obtained for the first time via a thermodynamic approach which, up to TL, is as good as those obtained via the earlier approaches. While this is interesting per se, another significant result of this paper is that for T TL it corroborates the result of the BSE-based approach.
文摘采用溶胶-凝胶法制备Y0.06Sr0.94Ti1-xFexO3-δ(x为原子分数。x=0.2,0.3,0.4,0.5)混合导体材料,用X射线衍射(XRD)分析该材料的物相,采用交流阻抗法和电子阻塞电极法分别测定其总电导率与离子电导率,研究铁含量对Y0.06Sr0.94TiO3混合导体材料的结构及电性能的影响。结果表明该材料属于单一立方相钙钛矿结构;在测试温度范围内,Y0.06Sr0.94Ti1-xFexO3-δ的总电导率和离子电导率都随温度升高而增大;随 Fe 掺杂量增加,总电导率和离子电导率都增大。在800℃下Y0.06Sr0.94Ti1-xFexO3-δ(x=0.2,0.3,0.4,0.5)的总电导率为0.019~0.12 S/cm,离子电导率为0.0106~0.0153 S/cm。根据传导活化能可以看出,x从0.3增加到0.4时材料的传导机制发生改变。