Fig. 2

(First column) (a) Intensity-correlated QFRS for time-evolving electronic coherence versus the delay T between entangled photons and resonant pump pulse; b Same as a but for heterodyne detection. c, d Same as a, b but using classical pulse as probe having bandwidth σ₀ = 0.82eV. e, f Same as a, b but using uncorrelated separable state of photons with the bandwidth σ₀ = 0.82eV (\({\sigma }_{0}^{-1}=5\)fs). F_j and D_j denote the couplings to high-frequency vibrations and other low-energy degrees of freedom; F₁ = 2.2, F₂ = 1.3, \({D}_{1}^{-1/2}=30\)fs, \({D}_{2}^{-1/2}=20\)fs. Other parameters are taken from 4-oriented amino-4’nitrostilbene⁶³, i.e., \({\omega }_{{e}_{1}}=5.3\)eV, \({\omega }_{{e}_{2}}=5.7\)eV, \({\omega }_{{e}_{3}}=7.1\)eV, v_h = 0.26eV and T_s = T_i = 30fs