Collective and individual excitations in a linear atomic chain

Upon interaction between light and matter, particularly in solid-state materials, elementary excitations can be classified into collective and individual excitations. In this theoretical study, we investigate the interaction between a linear atomic chain and a linearly polarized laser field. Our findings reveal that both plasmon resonance, a form of collective excitation, and high harmonic generation, which arises from individual excitation, can occur simultaneously. The signals from these excitations exhibit different dependencies on the parameters of the atomic chain and the laser pulse. By adjusting factors such as pulse width, the relative intensities of these excitations can be controlled. The ability to observe and manipulate this dual excitation mode in a solid-state system lays the groundwork for further research into laser–matter interactions.