Magnetic field dependence of low-energy magnetic correlations in Nd2-xCexCuO4

Strongly Ce doped Nd2 - xCexCuO4 exhibits heavy-fermion like behavior due t o a supposed 4f-3d electron hybridization. The magnetic response seen by in elastic neutron scattering can be divided into contributions from correlate d Nd3+ spins, reminiscent of the spin waves in undoped Nd2CuO4, and from in dependent, slowly relaxing Nd3+ spins. By applying a magnetic held along [0 1 0] the quasi-elastic scattering disappears and a transition into a parti ally aligned phase is generated at about 3.7 T. The critical held correspon ds to the re-appearance of the Schottky peak in the specific heat. Elastic measurements confirm the low-dimensional character of the magnetic structur e of the highly Ce doped compound and suggest a change of the spin structur e compared to Nd2CuO4. (C) 1999 Elsevier Science B.V. All rights reserved.