Modulus squares of the overlap of different initial states, with the initial population of the excited states p = 0 (black), 0.05 (red), 0.1 (blue), and 0.15 (green) (from top to bottom) for Ω₀ = 0, δ₀ = 0, δ₁ = 1.5κ, and Ω₁ = 4.0κ.