Multiferroic materials that exhibit vertical magnetic anisotropy (PMA) coupled with ferroelectricity are of critical importance for the development of spintronic and quantum functional devices. However, current efforts to regulate such materials—mainly focusing on spin- or orbital-related degrees of freedom—have yielded limited success.

In conventional displacement-type multiferroics, the well-known d⁰ rule severely restricts the magnetic structure design necessary for tunable ferromagnetism–ferroelectricity coupling. Meanwhile, in non-intrinsic ferroelectric multiferroics, which depend on spin- or charge-driven polarization mechanisms, challenges arise due to typically weak spontaneous polarization, low Curie temperatures, and especially weak ferromagnetic ordering that fails to induce strong PMA.

Thus, designing multiferroic materials with robust PMA and ferroelectric coupling, and uncovering the intrinsic mechanism that enables simultaneous control of ferroic orders, remains a major and challenging frontier in condensed matter physics.

Building on their previous discovery of a hybrid improper ferroelectric (HIF) mechanism in La₂NiMnO₆/La₂CoMnO₆ (LNMO/LCMO) double perovskite superlattices [Nature Communications, 2024, 15(1): 5549], the team led by Professor Zhao Shifeng from the Key Laboratory of Microscale Physics and Atomic Manufacturing of Inner Mongolia Autonomous Region and the School of Physical Science and Technology has now proposed a geometric control strategy.

This strategy couples oxygen octahedral rotation/tilt modes with Jahn-Teller (JT) distortions within the superlattice, achieving a co-regulation of PMA and HIF.

The research has been accepted for publication in Physical Review Letters, one of the most prestigious journals in the field of physics. This achievement marks a major advancement in the design of next-generation multiferroic materials and showcases Inner Mongolia University’s leading-edge contributions to the field of magnetoelectric coupling and functional materials physics.