Many-body phenomena are paramount in physics. In condensed matter, their hallmark is considerable on a wide range of material characteristics spanning electronic, magnetic, thermodynamic and transport properties. They potentially imprint non-trivial signatures in spectroscopic measurements, such as those assigned to Kondo, excitonic and polaronic features, whose emergence depends on the involved degrees of freedom. Here, we address systematically zero-bias anomalies detected by scanning tunneling spectroscopy on Co atoms deposited on Cu, Ag and Au(111) substrates, which remarkably are almost identical to those obtained from first-principles. These features originate from gaped spin-excitations induced by a finite magnetic anisotropy energy, in contrast to the usual widespread interpretation relating them to Kondo resonances. Resting on relativistic time-dependent density functional and many-body perturbation theories, we furthermore unveil a new many-body feature, the spinaron, resulting from the interaction of electrons and spin-excitations localizing electronic states in a well defined energy.

多体现象在物理学中至关重要。在凝聚态物质中，它们在广泛的材料特性（包括电子，磁性，热力学和传输特性）方面具有可观的标志。它们可能会在光谱测量中留下非平凡的印记，例如分配给近藤，激子和极化特征的那些，其出现取决于所涉及的自由度。在这里，我们系统地解决了通过扫描隧道光谱法对沉积在Cu，Ag和Au（111）衬底上的Co原子检测到的零偏压异常现象，这些异常现象与从第一原理中获得的误差几乎相同。这些特征源自有限的磁各向异性能引起的带隙自旋激发，这与将其与近藤共振相关的通常的广泛解释相反。