Strong intrinsic multiferroism and magnetoelectric coupling in (1-x)BiFeO3-(x)BaTiO3 films

• 成果类型: Article
• 署名作者: Kim, Tae Yeon; Schimpf, Jesse; Paul, Atanu; Xu, Michael; Samanta, Atanu; Husain, Sajid; Meisenheimer, Peter; Harris, Isaac; Finkel, Peter; Mion, Thomas; Staruch, Margo; Ruffino, Anthony J.; Masiuk, Stefan; Wu, Liyan; Park, Tae Joon; Kang, Deokyoung; Klewe, Christoph; Stevenson, Paul; Ramesh, Ramamoorthy; Rappe, Andrew M.; LeBeau, James M.; Spanier, Jonathan E.; Grinberg, Ilya; Martin, Lane W.
• 署名单位: Rice University; Rice University; University of California System; University of California Berkeley; Bar Ilan University; Massachusetts Institute of Technology (MIT); University of Pennsylvania; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; University of California System; University of California Berkeley; Drexel University; Drexel University; Korea University; Northeastern University; Rice University; Rice University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.2603475123
• 发表日期: 2026-05-05
• 页码: e2603475123
• 关键词: multiferroic; single-phase; epitaxial thin-film; magnetoelectric coupling; temperature; dependence; VACANCY

摘要

The coexistence of ferroelectric and antiferromagnetic order in BiFeO3 makes it promising for next-generation magnetoelectric devices. But, single-phase multiferroics with robust room-temperature polarization and magnetization are rare. Here, enhanced, room-temperature ferroelectric polarization (approximate to 120 & micro;C cm-2), saturation magnetization (approximate to 40 emu cm-3), and strong magnetoelectric coupling (approximate to 400 mV cm-1 Oe-1) are observed in epitaxial (1-x)BiFeO3-(x)BaTiO3 thin films. These values of magnetization and magnetoelectric coupling are, respectively, one- and two-orders of magnitude larger than those same properties in the widely studied parent material BiFeO3. This sought after combination of properties is found in a distinct tetragonal phase, which is different from rhombohedral and super-tetragonal variants of BiFeO3, that emerges at x = 0.2 to 0.3 via combined chemical substitution and epitaxial strain. Structural and physical-property characterization, along with first-principles calculations, reveal a transition from monoclinic to tetragonal symmetry and suggest that short-range ordering of the titanium in the tetragonal phase results in ferrimagnetic spin ordering. This work demonstrates a unique single-phase multiferroic combining strong polarization, magnetization, and magnetoelectric coupling achieved through manipulation of the coupled chemical order and spin order; thereby addressing a major challenge in multiferroics research and providing a path toward practical room-temperature, efficient charge-to-spin and spin-to-charge conversion technologies.