Excitonic effects in third harmonic generation: the case of carbon nanotubes and nanoribbons

Abstract

Linear and nonlinear optical properties of low dimensional nanostructures have attracted a large interest in the scientific community as tools to probe the strong confinement of the electrons and for possible applications in optoelectronic devices. In particular it has been shown that the linear optical response of carbon nanotubes [Science 308, 838 (2005)] and graphene nanoribbons [Nat. Comm. 5, 4253 (2014)] is dominated by bounded electron-hole pairs, the excitons. The role of excitons in linear response has been widely studied, but still little is known on their effect on nonlinear susceptibilities. Using a recently developed methodology [Phys. Rev. B 88, 235113 (2013)] based on well-established ab-initio many-body perturbation theory approaches, we find that quasiparticle shifts and excitonic effects significantly modify the third-harmonic generation in carbon nanotubes and graphene nanoribbons. For both systems the net effect of many-body effects is to reduce the intensity of the main peak in the independent particle spectrum and redistribute the spectral weight among several excitonic resonances.

References in corpus (5)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Energy Gaps in Graphene Nanoribbons
• Optical properties of graphene nanoribbons: the role of many-body effects
• Third harmonic generation in graphene and few-layer graphite films
• Optical second harmonic generation from Wannier excitons

Cited by in corpus (5)

• Many-body perturbation theory calculations using the yambo code
• Topologically localized excitons in single graphene nanoribbons
• Electric field induced injection and shift currents in zigzag graphene nanoribbons
• Plasmons in phosphorene nanoribbons
• Floquet formulation of the dynamical Berry-phase approach to non-linear optics in extended systems