Exploring metamagnetism of single crystalline EuNiGe$_3$ by neutron scattering

Xavier Fabrèges (1) , Arsen Gukasov (1) , Pierre Bonville (2) , A Maurya (3) , A Thamizhavel (3) , S K Dhar (3)

1 LLB - UMR 12 - Laboratoire Léon Brillouin
2 LNO - Laboratoire Nano-Magnétisme et Oxydes
3 CMPMS - Department of Condensed Matter Physics and Materials Science [TIFR]

We present here a neutron diffraction study, both in zero field and as a function of magnetic field, of the magnetic structure of the tetragonal intermetallic EuNiGe$_3$ on a single crystalline sample. This material is known to undergo a cascade of transitions, first at 13.2 K towards an incommensurate modulated magnetic structure, then at 10.5 K to an antiferromagnetic structure. We show here that the low-temperature phase presents a spiral moment arrangement with wave vector $k$ = ($1\over 4$ ,δ,0). For a magnetic field applied along the tetragonal $c$ axis, the square root of the scattering intensity of the (1 0 1) reflection matches very well the complex metamagnetic behavior of the magnetization along $c$ measured previously. For the magnetic field applied along the $b$ axis, two magnetic transitions are observed below the transition to a fully polarized state.

Mots clés: metamagnetism; mean field theory; Neutron scattering

Domaines: Physique [physics]; Matière Condensée [cond-mat]

Xavier Fabrèges, Arsen Gukasov, Pierre Bonville, A Maurya, A Thamizhavel, et al.. Exploring metamagnetism of single crystalline EuNiGe$_3$ by neutron scattering. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2016, 93, pp.214414. ⟨10.1103/PhysRev.120.91⟩. ⟨cea-01550620⟩