论文标题
通过NMR绘制共掺杂的Lafeaso单晶的自旋波动
Mapping out the spin fluctuations in Co-doped LaFeAsO single crystals by NMR
论文作者
论文摘要
我们通过使用核磁共振（NMR）来确定Lafe $ _ {1-X} $ CO $ _X $ ASO单晶的相位图。最多达到$ x = 0.03 $的名义掺杂，它遵循F掺杂多晶的相图。高于$ x = 0.03 $，F掺杂样品成为超导，而对于共同掺杂结构和磁过渡，可以观察到$ x = 0.042 $，并且超导性仅用于较高的兴奋剂水平，并且过渡温度降低。对于最大$ x = 0.056 $的兴奋剂，我们找到了短距离磁性顺序的证据。通过弛豫率测量，我们绘制出揭示了nematicity和磁性相互作用的磁波动。在上面的订购之上，Lafe $ _ {1-x} $ co $ _x $ aso中的自旋波动与BA（Fe $ _ {1-x} $ _x $ _x $）$ _ 2 $ as $ _2 $相同，这表明Lafeaso中的nematicity在Lafeaso中是一种结果，这是一个造成的旋转旋转wave。
We determine the phase diagram of LaFe$_{1-x}$Co$_x$AsO single crystals by using nuclear magnetic resonance (NMR). Up to a nominal doping of $x=0.03$, it follows the phase diagram for F-doped polycrystals. Above $x=0.03$, the F-doped samples become superconducting, whereas for Co-doping the structural and magnetic transitions can be observed up to $x=0.042$, and superconductivity occurs only for higher doping levels and with reduced transition temperatures. For dopings up to $x=0.056$, we find evidence for short-range magnetic order. By means of relaxation-rate measurements, we map out the magnetic fluctuations that reveal the interplay of nematicity and magnetism. Above the nematic ordering, the spin fluctuations in LaFe$_{1-x}$Co$_x$AsO are identical to those in Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$, suggesting that nematicity in LaFeAsO is a result of the fluctuating spin density wave as well.
