Figure 3: Magnetic structure and magnetic excitations probed through neutron-scattering experiments.

(a) Temperature evolution of the sum of the integrated intensities of the 10, 11
and 21
magnetic reflections (open circles). (b) Magnetic structure of a single square cupola layer. Expected direction of electric polarization P in each square cupola induced by a magnetic field (B) along the [100] direction is indicated. (c) Detailed configuration of magnetic moments in square cupolas A and B. (d) Inelastic neutron powder intensity map at 2 K as a function of momentum |Q| and energy E transfer. Measurements were recorded from a powder sample using incident neutron energy of 6 meV. (e) A constant-|Q| cut integrated between 1.3<|Q|<1.6 Å−1 at 2 and 30 K.