Hexagonal Manganites—(RMnO₃): Class (I) Multiferroics with Strong Coupling of Magnetism and Ferroelectricity

Figure 31

Magnetic phase diagrams and magnetic symmetries of RMnO₃ (R = Ho, Er, Tm, Yb) as derived from SHG optical experiments. The symbols 𝐴_𝑖 and 𝐵_𝑖 denote the following magnetic space groups: 𝐴₁=𝑃6₃𝑐𝑚, 𝐴₂=𝑃6₃𝑐𝑚, 𝐵₁=𝑃6₃𝑐𝑚, and 𝐵₂=𝑃6₃𝑐𝑚. Reprinted with permission from [93].