The suppression of magnetic order with pressure concomitant with the appearance of pressure- induced superconductivity was recently discovered in CrAs. Here we present a neutron diffraction study of the pressure evolution of the helimagnetic ground-state towards and in the vicinity of the superconducting phase. Neutron diffraction on polycrystalline CrAs was employed from zero pressure to 0.65 GPa and at various temperatures. The helimagnetic long-range order is sustained under pressure and the magnetic propagation vector does not show any considerable change. The average ordered magnetic moment is reduced from 1.73(2) {\mu}B at ambient pressure to 0.4(1) {\mu}B close to the critical pressure Pc=0.7 GPa, at which magnetic order is completely suppressed. The width of the magnetic Bragg peaks strongly depends on temperature and pressure, showing a maximum in the region of the onset of superconductivity. We interpret this as associated with competing ground-states in the vicinity of the superconducting phase.
@article{arxiv.1409.5706,
title = {Pressure dependence of the magnetic order in CrAs: a neutron diffraction investigation},
author = {L. Keller and J. S. White and M. Frontzek and P. Babkevich and M. A. Susner and Z. C. Sims and A. S. Sefat and H. M. Ronnow and Ch. Rüegg},
journal= {arXiv preprint arXiv:1409.5706},
year = {2015}
}