From the electrical resistivity and ac susceptibility measurements down to T = 40 mK, a rich temperature-field phase diagram has been constructed for the geometrically frustrated heavy-fermion compound CePdAl. In the limit of zero temperature, the field-induced suppression of the antiferromagnetism in this compound results in a sequence of phase transitions/corssovers, rather than a single critical point, in a critical region of field 3−5 T. In the lowest temperature region, a power-law description of the temperature-dependent resistivity yields A⋅Tn with n>2 for all applied fields. However, a quadratic-in-temperature resistivity term can be extracted when assuming an additional electron scattering channel from magnon-like excitations, with A diverging upon approaching the critical regime. Our observations suggest CePdAl to be a new playground for exotic physics arising from the competition between Kondo screening and geometrical frustration.
@article{arxiv.1608.07123,
title = {Temperature-field phase diagram of geometrically frustrated CePdAl},
author = {Hengcan Zhao and Jiahao Zhang and Sile Hu and Yosikazu Isikawa and Jianlin Luo and Frank Steglich and Peijie Sun},
journal= {arXiv preprint arXiv:1608.07123},
year = {2016}
}