Quantum phase transition in Pr2CuO4 to collinear non spin-flop state in magnetic field: A neutron diffraction study
In the external field applied to the tetragonal antiferromagnet Pr2CuO4, a transition is discovered from the phase with orthogonal antiferromagnetic spin subsystems along [1,0,0] and [0,1,0] to the phase with collinear spins, which are inclined about 45° to the field. This phase is shown to be due to the interplane pseudodipolar interaction, and transforms into the spin-flop phase (S⊥H) asymptotically at very high field. The discovered phase transition is of first order, if the field is along [1,0,0], or [0,1,0], and becomes of second order if the field is slightly inclined to these axes. It holds at T = 0 and is a quantum one, with the transition field being the critical point and the angle between two subsystems below the critical point being the order parameter.
EPL (Europhysics Letters)
- Pub Date:
- February 2003
- Spin arrangements in magnetically ordered materials;
- Magnetic phase boundaries;
- Condensed Matter - Strongly Correlated Electrons