Coulomb interaction effects on nonlinear optical response in C60, C70, and higher fullerenes

Abstract

Nonlinear optical properties in the fullerene C${}_{60}$ and the extracted higher fullerenes -- C${}_{70}$, C${}_{76}$, C${}_{78}$, and C${}_{84}$ -- are theoretically investigated by using the exciton formalism and the sum-over-states method. We find that off-resonant third order susceptibilities of higher fullerenes are a few times larger than those of C${}_{60}$. The magnitude of nonlinearity increases as the optical gap decreases in higher fullerenes. The nonlinearity is nearly proportional to the fourth power of the carbon number when the onsite Coulomb repulsion is $2t$ or $4t$, $t$ being the nearest neighbor hopping integral. This result, indicating important roles of Coulomb interactions, agrees with quantum chemical calculations of higher fullerenes.

8 pages; 3 figures; Figures should be requested to the author (E-mail: [email protected])

References in corpus (4)

• Optical absorption spectra in fullerenes C60 and C70: Effects of Coulomb interactions, lattice fluctuations, and anisotropy
• Dispersion of the Third-Order Nonlinear Optical Susceptibility in C_{60} Calculated with a Tight-Binding Model
• Nonlinear Optical Response of C60 Molecules
• Optical absorption spectra and geometric effects in higher fullerenes

Cited by in corpus (1)

• Effects of Lagrangian Multipliers on SWCNT in Real Space