Harmonic generations of cluster Na₂ in ultrashort intense laser pulses

In the framework of the time dependent local density approximation the harmonic generation of Na₂ in ultrashort intense pulses is investigated. The coupling between harmonics and plasmons of Na₂ is discussed in detail with two laser frequencies 5.266 eV, which is double the resonance of the plasmon, and 1.124 eV, which is half the frequency of plasmons, and with two different peak intensities. One finds appearance of the third and the fifth harmonic generation at high ponderomotive potential.