At the interface of classical and quantum physics, the Maxwell and Schrödinger equations describe how optical fields drive and control electronic phenomena to enable lightwave electronics at terahertz or petahertz frequencies and on ultrasmall scales1-5. The electric field of light striking a metal interacts with electrons and generates light-matter quasiparticles, such as excitons6 or plasmons7, on an attosecond timescale. Here we create and image a quasiparticle of topological plasmonic spin texture in a structured silver film. The spin angular momentum components of linearly polarized light interacting with an Archimedean coupling structure with a designed geometric phase generate plasmonic waves with different orbital angular momenta. These plasmonic fields undergo spin-orbit interaction and their superposition generates an array of plasmonic vortices. Three of these vortices can form spin textures that carry non-trivial topological charge8 resembling magnetic meron quasiparticles9. These spin textures are localized within a half-wavelength of light, and exist on the timescale of the plasmonic field. We use ultrafast nonlinear coherent photoelectron microscopy to generate attosecond videos of the spatial evolution of the vortex fields; electromagnetic simulations and analytic theory confirm the presence of plasmonic meron quasiparticles. The quasiparticles form a chiral field, which breaks the time-reversal symmetry on a nanometre spatial scale and a 20-femtosecond timescale (the 'nano-femto scale'). This transient creation of non-trivial spin angular momentum topology pertains to cosmological structure creation and topological phase transitions in quantum matter10-12, and may transduce quantum information on the nano-femto scale13,14.

中文翻译：

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纳米和飞秒尺度上的等离子体拓扑准粒子

在经典物理学和量子物理学的接口处，麦克斯韦方程和薛定谔方程描述了光场如何驱动和控制电子现象，以实现太赫兹或太赫兹频率以及超小尺度1-5 的光波电子学。撞击金属的光电场与电子相互作用并在阿秒时间尺度上产生光物质准粒子，例如激子 6 或等离子激元 7。在这里，我们在结构化的银膜中创建并成像了拓扑等离子体自旋纹理的准粒子。线偏振光的自旋角动量分量与具有设计几何相位的阿基米德耦合结构相互作用，产生具有不同轨道角动量的等离子体波。这些等离子体场经历自旋轨道相互作用，它们的叠加会产生一系列等离子体涡旋。其中三个漩涡可以形成自旋纹理，带有类似磁性子准粒子 9 的非平凡拓扑电荷 8。这些自旋纹理位于光的半波长内，并存在于等离子体场的时间尺度上。我们使用超快非线性相干光电子显微镜来生成涡旋场空间演化的阿秒视频；电磁模拟和解析理论证实了等离子子准粒子的存在。准粒子形成手征场，打破了纳米空间尺度和 20 飞秒时间尺度（“纳米飞秒尺度”）上的时间反转对称性。