Gu Mingqiang, Liu Yuntian, Zhu Haiyuan, Yananose Kunihiro, Chen Xiaobing, Hu Yongkang, Stroppa Alessandro, Liu Qihang
Southern University of Science and Technology, Department of Physics and Guangdong Basic Research Center of Excellence for Quantum Science, Shenzhen 518055, China.
Korea Institute for Advanced Study, Seoul 02455, Republic of Korea.
Phys Rev Lett. 2025 Mar 14;134(10):106802. doi: 10.1103/PhysRevLett.134.106802.
We propose a novel ferroelectric switchable altermagnetism effect: the reversal of ferroelectric polarization is coupled to the switching of altermagnetic spin splitting. We demonstrate the design principles for the ferroelectric altermagnets and the additional symmetry constraints necessary for switching the spin splitting through flipping the electric polarization based on the state-of-the-art spin-group symmetry techniques. We find 22 ferroelectric altermagnets by screening through the 2001 experimental reported magnetic structures in the MAGNDATA database and identify two of them as ferroelectric switchable altermagnets. Using the hybrid improper ferroelectric material [C(NH_{2}){3}] Cr(HCOO){3} as an example, we show how the altermagnetic spin splitting is tightly coupled to the ferroelectric polarization, providing an ideal platform for designing electric-field-controllable multiferroic devices. Finally, we find that such manipulation of altermagnetism can be detected by monitoring the physical quantities that are related to the nonvanishing Berry curvature dipole, such as the linearly polarized photogalvanic spin current.
铁电极化的反转与交变磁自旋分裂的切换相耦合。我们基于最新的自旋群对称技术，展示了铁电交变磁体的设计原理以及通过翻转电极化来切换自旋分裂所需的额外对称约束。通过在MAGNDATA数据库中筛选2001个实验报道的磁结构，我们发现了22种铁电交变磁体，并将其中两种确定为铁电可切换交变磁体。以混合非本征铁电材料[C(NH₂)₃] Cr(HCOO)₃为例，我们展示了交变磁自旋分裂如何与铁电极化紧密耦合，为设计电场可控的多铁性器件提供了理想平台。最后，我们发现可以通过监测与非零贝里曲率偶极相关的物理量，如线性偏振光电流，来检测这种对交变磁性的操控。
