Optical high harmonic generation in C60 -: art. no. 047401

High harmonic generation (HHG) requires a strong laser field, but in C-60 a relatively weak laser field is sufficient. Numerical results presented here show that, while its low order harmonics result from the laser field, its high order ones are mainly from the multiple excitations. Since high order harmonics directly correlate with electronic transitions, the HHG spectrum accurately measures transition energies. Therefore, C-60 is not only a promising material for HHG, but may also present an opportunity to develop HHG into an electronic structure probing tool.