论文标题
LAO1-XFXBISSE的结构相图：抑制部分F取代的结构相变
Structural phase diagram of LaO1-xFxBiSSe: suppression of the structural phase transition by partial F substitutions
论文作者
论文摘要
我们已经研究了基于BICH2的化合物的低温晶体结构LAO1-XFXBISSE（X = 0、0.01、0.01、0.02、0.03和0.5），其中对X = 0.5的超导状态的异常二倍对称态度的超对面状态异常。从同步加速器X射线衍射实验中，分别在340和240 K时观察到了从四方到单斜胶的结构过渡。对于X = 0.03，未观察到衍射峰的结构过渡和拓宽至100K。这些事实表明，在LAO1-XFXBISSE中，3％F取代可以抑制结构过渡。此外，通过低温（实验室）X射线衍射检查了4 K时X = 0.5的晶体结构，该衍射证实了四方结构在4 K下保持在4 K，x = 0.5。我们的结果表明，在LAO0.5F0.5BISSE观察到的超导状态的两倍对称面内各向异性不是源于结构对称性的降低。
We have investigated low-temperature crystal structure of BiCh2-based compounds LaO1-xFxBiSSe (x = 0, 0.01, 0.02, 0.03, and 0.5), in which anomalous two-fold-symmetric in-plane anisotropy of superconducting states has been observed for x = 0.5. From synchrotron X-ray diffraction experiments, a structural transition from tetragonal to monoclinic was observed for x = 0 and 0.01 at 340 and 240 K, respectively. For x = 0.03, a structural transition and broadening of the diffraction peak were not observed down to 100 K. These facts suggest that the structural transition could be suppressed by 3% F substitution in LaO1-xFxBiSSe. Furthermore, the crystal structure for x = 0.5 at 4 K was examined by low-temperature (laboratory) X-ray diffraction, which confirmed that the tetragonal structure is maintained at 4 K for x = 0.5. Our results suggest that the two-fold-symmetric in-plane anisotropy of superconducting states observed for LaO0.5F0.5BiSSe was not originated from structural symmetry lowering.
