High-energy spin excitations in heavily electron-doped Pr 1-xLaCexCuO4

Abstract

We performed neutron scattering measurements on the overdoped sample of electron-doped superconductor Pr0.83LaCe0.17CuO 4 (Tc∼16 K) to clarify an overall spin excitation spectrum. Clear commensurate low-energy spin fluctuations were observed at the (π, π) reciprocal position below ∼10 meV. With increasing energy transfer, the width of commensurate peak drastically broadens and the intensity rapidly decreases. However, magnetic scattering intensities at high-energy region around 100 meV were confirmed to exist. These results are quantitatively same with those obtained for optimally-doped Pr0.89LaCe 0.11CuO4, while the broadening of peak-width against energy transfer is more marked and the intensities at high-energy region are weaker in the present overdoped sample. Detailed comparison of excitation spectra with the optimally-doped sysmte is given. © 2008 IOP Publishing Ltd.