Resonant ultrafast excitation of infrared-active phonons is a powerful technique with which to control the electronic properties of materials that leads to remarkable phenomena such as the light-induced enhancement of superconductivity^1,2, switching of ferroelectric polarization^3,4 and ultrafast insulator-to-metal transitions⁵. Here, we show that light-driven phonons can be utilized to coherently manipulate macroscopic magnetic states. Intense mid-infrared electric field pulses tuned to resonance with a phonon mode of the archetypical antiferromagnet DyFeO₃ induce ultrafast and long-living changes of the fundamental exchange interaction between rare-earth orbitals and transition metal spins. Non-thermal lattice control of the magnetic exchange, which defines the stability of the macroscopic magnetic state, allows us to perform picosecond coherent switching between competing antiferromagnetic and weakly ferromagnetic spin orders. Our discovery emphasizes the potential of resonant phonon excitation for the manipulation of ferroic order on ultrafast timescales⁶.

红外活性声子的共振超快激发是一种强大的技术，可用于控制材料的电子特性，从而导致显着的现象，例如光诱导的超导增强^1,2、铁电极化的切换^3,4和超快绝缘体-金属过渡⁵ . 在这里，我们展示了光驱动声子可用于连贯地操纵宏观磁态。强中红外电场脉冲调谐到与原型反铁磁体 DyFeO _{3的声子模式共振}诱导稀土轨道和过渡金属自旋之间的基本交换相互作用的超快和长期变化。磁交换的非热晶格控制定义了宏观磁态的稳定性，使我们能够在竞争的反铁磁和弱铁磁自旋顺序之间进行皮秒相干切换。我们的发现强调了共振声子激发在超快时间尺度上操纵铁序⁶的潜力。