0 1.5e+05 a 0 0.2 0.4 0.6 0.8 1 population 0 1.5e+05 b 0 1.5e+05 c FIG. 4: Population dynamics in three-level λ -system, reached using an optical frequency comb as in Eq.(1) with different values of the modulation amplitude equal to Φ 0 =3.(a), Φ 0 =5.(b), Φ 0 =8.(c). Other parameters are the effective Rabi frequency Ω$_{R}$=1, (70THz), the carrier frequency ω$_{L}$ =5.9, (410.7 THz), and the modulation frequency Ω=4.9, (340.7 THz). For all three values of Φ 0 , there is only partial population transfer to the final state | 3 > , (green), unlike to the solution for Φ 0 = 4 . in Fig.(2). 2 4 6 8 10 12 14 Ω 0.2 0.4 0.6 0.8 E $^{2}$GLYPH<LParen1> Ω GLYPH<RParen1> FIG. 5: The envelope of the power spectrum of the optical frequency comb as in Eq.(1), (no dense radio frequency comb lines are included). The pulse train parameters are the effective Rabi frequency Ω$_{R}$=1, (70THz), the carrier frequency ω$_{L}$ =5.9 ,(410.7 THz), the modulation frequency Ω=4.9, (340.7 THz), and the modulation amplitude Φ 0 =3. (red), Φ 0 =4. (green), Φ 0 =5. (blue), Φ 0 =8. (black). 8