Behavior of Sm in the boron cage of Sm-doped RB6 (R=Yb, La) observed by multiple-wavelength neutron holography

Using multiple-wavelength neutron holography (MNH), the behavior of Sm in 2% Sm-doped $R$B${}_{6}$ ($R$=La, Yb) is quantitatively evaluated. This work reveals that the fluctuation of Sm in YbB${}_{6}$ is 1.5 times larger than in LaB${}_{6}$. Furthermore, Sm doping causes lattice distortions that are limited to only the nearest neighboring B, while the effects on $R$ and more distant B atoms are negligible. MNH is effective for the direct visualization of local atomic structures around dopants, particularly light elements.