One‐Dimensional Acoustic Plasmons in Metallic Single‐Walled Carbon Nanotubes

ABSTRACT Acoustic plasmons, collective out‐of‐phase oscillations of image charges, can confine electric fields with exceptional strength, making them highly effective for applications requiring intense field localization. Here, we predict the existence of one‐dimensional (1D) acoustic plasmons in metallic single‐walled carbon nanotubes (SWNTs) on metallic substrates. These 1D acoustic plasmons achieve intensive electric field concentration with the plasmon wavelength contracted by approximately 22% compared to 1D plasmons in SWNTs. Because 1D plasmons in SWNTs are described by Luttinger liquid theory which captures the interactions among electrons in one‐dimensional systems, we anticipate that 1D acoustic plasmons can control quantum properties of the Luttinger liquid through optical and electrical means.