Origins of↑↑↓↓magnetic structure and ferroelectricity in multiferroicLu2CoMnO6

Improper ferroelectricity at antiferromagnetic domain walls of perovskite oxides

“…2, which supports the validity of the model used here and thus also explains the (symmetric exchange striction) origin of the polarizations reported in Table I. Note that these types of interactions also explain why a polarization was recently found along the b axis in some double-perovskite A 2 BB'O 6 oxides (that are systems possessing two different chemically-ordered B sites) exhibiting magnetic domain walls [19][20][21]. Interestingly, one of the structures determined in Ref.…”

“…Indeed, here we would like to explore if another mechanism can generate an electrical polarization in SmFeO 3 or, more generally, in rare-earth orthoferrites or rare-earth orthochromites sharing the same atomic structure and possessing magnetic ordering of the Fe or Cr spins. More precisely, we wish to determine if the finding recently made in double perovskite systems [18][19][20][21] can be generalized to SmFeO 3 and rare-earth orthoferrites or orthochromites, with quantitative formulation of polarization arisen as a result of antiferromagnetic domain anti-phase boundaries. The aims of this paper are to reveal that how magnetic domain boundaries can indeed generate a polarization (along a specific direction) in such compounds, and to provide the microscopic features and precise driving mechanisms of such polarization, by using and analyzing first-principles simulations.…”

“…Moreover, the significant displacement of the O ions being located at the domain walls along the +b direction (see Fig. 3) makes the angle of Fe-O-Fe bonds (being initially aligned along the c-axis) decreasing, which reduces the magnitude of the antiferromagnetic exchange interaction according to the Goodenough-Kanamori rule [20,51] and in turn affects the polarization coefficient vectors [49].…”

Single Crystal Growth of Multiferroic Double Perovskites: Yb2CoMnO6 and Lu2CoMnO6

“…Recently, a new type-II multiferroic was discovered: a double-perovskite structure of Lu 2 CoMnO 6 [14][15][16][17]. From the polycrystalline work, the ferroelectricity was predicted to be along the crystallographic c axis originating from the symmetric exchange striction of the up-up-down-down (↑↑↓↓) spin arrangement with alternating charge valences [15,17,18].…”

“…From the polycrystalline work, the ferroelectricity was predicted to be along the crystallographic c axis originating from the symmetric exchange striction of the up-up-down-down (↑↑↓↓) spin arrangement with alternating charge valences [15,17,18]. However, previous studies on single crystals revealed ferroelectricity perpendicular to the c axis, which can be explained by the net polarization induced by the uniform oxygen displacements perpendicular to the c axis on neighboring ↑↑↓↓ spin chains when the symmetric exchange striction is activated [16][17][18]. Lu 2 CoMnO 6 belongs to the double-perovskite RE 2 CoMnO 6 series (RE = La, .…”