, FUNDAMENTALS OF (MULTI-)FERROICS

T. .. >-t-c-and-t-<-t-c,

. , Temperature dependence of the order parameter (a) Q and (b) P and (c) the electric susceptibility ? for improper ferroelectrics

, Temperature dependence of the order parameter (a) Q and (b) P and (c) the electric susceptibility ? for pseudo-proper ferroelectrics

. , Crystal structure of orthorhombic RM O 3 with P bnm space group and its cubic prototype, visualized by VESTA [14]

. .. , Conventional collinear spin orders in P bnm unit cell, p.11

. , Experimentally obtained magnetoelectric phase diagram of RMnO 3 and solid-solution systems in the plane of temperature and (effective) ionic radius of the R ion [15]

. , Magnetic and dielectric anomalies of TbMnO 3

. , Three types of spin density wave from expression (1.38)

, Unit cell of two kinds E-AFM order in P bnm space group, p.19

E. Two and .. .. Collinear-spin-orders,

. , B-site) are shown. J ab and J c are the in-plane and out-of-plane nearest interactions, while J a is the in-plane next-nearest interaction, Schematic diagram of exchange interactions in P bnm lattice, for simplicity, only magnetic atoms

, Dzyaloshinsky-Moriya interactions associated with different Mn-O-Mn bonds, Mn is in blue and O is in red, the A-site ions are neglected for simplicity, p.25

. , 15 (a) Phase diagram and (b) the corresponding ground states UUDD and (?, 0) (0, ?)

. , Magnetic and electric phase diagram of (a) the (010)-oriented and (b) the (001)-oriented TbMnO 3 thin film as well as (c) the (010)-oriented and (d) the (001)-oriented EuMnO 3 thin film

A. , Non-collinear spin-canted order

, Néel and spin-reorientation temperatures for the Fe spin order in RFeO 3 perovskites. Filled circles, open circles and squares indicate the establishment of spin order G x A y F z , F x C y G z and A x G y C z respectively, p.90

J. Of-gd-gd and F. .. Gd-fe, , p.92

, Atom magnetization as a function of temperature for GdFeO 3 , magnetization of Fe is labeled by red line, while that of Gd is by blue line, p.94

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