Enhanced anisotropic spin fluctuations below tetragonal-to-orthorhombic transition in LaFeAs(O_{1-x}F_x) probed by ^{75}As and ^{139}La NMR

Yusuke Nakai, Shunsaku Kitagawa, Tetsuya Iye +4

${}^{75}$As and ${}^{139}$La NMR results of LaFeAs(O${}_{1-x}$F${}_x$) ($x$=0, 0.025, and 0.04) were reported. Upon F-doping, the tetragonal-to-orthorhombic structural phase transition tem…