Comparison of absorption–dispersion and optical bistability behaviors between open and closed four-level tripod atomic systems |
(a) Probe absorption (b) dispersion, and (c) group velocity versus the probe detuning Δ p for closed (solid line) and open (dashed line) system J 1 = J 3 = 0.1, J 2 = 1.7 γ at θ = π /4. Other parameters are the same as those in Fig. 2 . |