Magnetic specific heat and susceptibility measurements on NdBa<inf>2</inf>Cu<inf>3-x</inf>Ga<inf>x</inf>O<inf>7-y</inf> at low temperatures

We report on the temperature dependence of magnetic specific heat and magnetic susceptibility results on Ga-substituted Nd-123 compounds at low temperatures. The magnetic ordering of the Nd3+ ions changes remarkably with increasing Ga concentration. The results are similar to those reported for pure undoped NdBa2Cu3O7-y samples when the oxygen content is reduced. The nature of the magnetic ordering is analysed using different magnetic models and the importance of crystalline electric field effects, in determining the nature of magnetic ordering, is emphasised. © 1995.