Nuclear spin excitations in Nd

We have investigated the low-energy excitations in Nd in the μeV range by a back-scattering neutron spectrometer. The energy scans on Nd revealed inelastic peaks at E=2.67±0.06 μeV at T=60 mK on both energy-gain and energy-loss sides. The inelastic peaks move gradually towards lower energy with increasing temperature, and finally merge with the elastic peak at zero energy transfer at the electronic magnetic ordering temperature TN∼19.8 K. At about 5 K we observe a second peak at E=1.8±0.3 μeV, which also decreases in energy with increasing temperature. This second peak disappears at about 15 K. We interpret the inelastic peaks as low-energy nuclear spin excitations arising due to the Suhl-Nakamura indirect interaction. (orig.)