Hall effect was studied on the single crystals of antiferromagnets PrB6 and NdB6 at temperatures 2K<T<300K in magnetic fields up to 8T using the sample rotation technique. At low magnetic fields μ0H≤1T Hall coefficient RH, which is practically temperature independent in paramagnetic state at 8K≤T≤70K, is characterized by the values of RH(PrB6)∼−(4.2±0.1)⋅10−4 cm3/C and RH(NdB6)∼−(4.1±0.1)⋅10−4 cm3/C. Rather different behaviour of RH is observed in antiferromagnetic (AF) phases of these hexaborides. For PrB6 the decrease of temperature below TN≈6.7K is accompanied by a noticeable (ΔRH/RH∼10) elevation of RH(μ0H=1T) to the values of −(3.8±0.1)⋅10−4 cm3/C. On the contrary, the low field Hall coefficient in NdB6 diminishes by about 15% reaching the value RH≈−(4.7±0.1)⋅10−4 cm3/C in AF state at 2.5K. The increase of magnetic field inducing magnetic transition in the commensurate magnetic phase of PrB6 results in essential RH changes (up to 10%) at liquid helium temperatures. The anomalous behaviour of the charge transport parameters for RB6 (R=Pr, Nd) found in vicinity of Neel temperature suggests the possible effect of 5d-states spin density polarization of both in AF and paramagnetic states of the compounds under investigation.
@article{arxiv.1006.0124,
title = {Hall effect in PrB$_6$ and NdB$_6$},
author = {M. A. Anisimov and A. V. Bogach and V. V. Glushkov and S. V. Demishev and N. A. Samarin and V. B. Filipov and N. Yu. Shitsevalova and N. E. Sluchanko},
journal= {arXiv preprint arXiv:1006.0124},
year = {2010}
}