Lago, J.Zivkovic, I.Malkin, B. Z.Rodriguez Fernandez, J.Ghigna, P.de Reotier, P. DalmasYaouanc, A.Rojo, T.2010-09-212010-09-212010-09-21201010.1103/PhysRevLett.104.247203https://infoscience.epfl.ch/handle/20.500.14299/54003WOS:000278773900001we present a detailed study of the spinel CdEr2Se4 and show it to be a new instance of spin ice, the first one in an erbium material and the first one in a spinel. Definitive experimental evidence comes from the temperature dependence of the magnetic entropy, which shows an excellent agreement with the predicted behavior for a spin ice state. Crystal field calculations demonstrate that the change in the local environment from that of the titanates completely alters the rare-earth anisotropy giving rise, in the case of Er3+, to the required Ising anisotropy, when Er2Ti2O7 behaves as an XY antiferromagnet. This finding opens up the possibility of new exotic ground states within the CdR2Se4 and CdR2Se4 families.Temperature Magnetic-PropertiesPyrochloresMonopolesHo2Ti2O7Entropytext::journal::journal article::research article