open access

https://hdl.handle.net/2115/92466

Grain engineered polar-axis-oriented epitaxial Mn2Mo3O8 films with enhanced magnetic transition temperature

英語

2023-05-16

Royal Society of Chemistry

Journal of materials chemistry C

Mn2Mo3O8 is a layered multiferroic material that exhibits unique properties such as two-dimensional magnetism, room-temperature ferroelectric order, and strong magnetoelectric coupling. However, it has a low magnetic transition temperature (T-N) of 41 K. Therefore, in this study, we grain engineered polar-axis-oriented Mn2Mo3O8 epitaxial films to enhance the T-N. Mn2Mo3O8 films were grown on yttria-stabilized zirconia (111) substrates. These films consisted of two types of hexagonal grains (G1 and G2) that were oriented at an angle of 30 degrees with respect to each other while maintaining the ferroelectric polar axis of the film along the out-of-plane direction. Such a dual grain system is a result of the layered structure of Mn2Mo3O8, in which the Mn and Mo layers are alternately stacked along the polar axis. The volume fraction of G2 was significantly affected by the film thickness and varied widely in the range 2-48%. Importantly, T-N of the grain engineered Mn2Mo3O8 films increased to 163 K with increasing the volume fraction. We speculate that this increase in T-N is due to the formation of a three-dimensional magnetic network at the grain boundaries.

学術雑誌論文

Accepted Manuscript

2050-7526