Sub-Doppler DAVLL signals in selective reflection scheme with magnetic fields and saturate absorption spectroscopy signals without magnetic fields. (a) The signals are related to the transitions of ⁸⁵Rb D₂ line. The black and red lines represent respectively the σ⁺ and σ⁻ polarized components of reflected spectrum of F = 3 to F ′ = 4 transition with magnetic field of 16.9 Gs. The green line represents saturate absorption spectroscopy signals, in which F ′ = 2 , F = 3, and F ′ = 4 show the transition of F = 3 to F ′ = 2 , 3 , 4 and CO23, CO24, CO34 mean the transition to 2–3, 2–4, and 3–4 crossover. (b) The signals are related to the transitions of ⁸⁷Rb D₂ line. The black and red lines represent respectively the σ⁺ and σ⁻ polarized components of reflected spectrum of F = 2 to F ′ = 3 transition with magnetic field of 12.7 Gs. The green line represents saturate absorption spectroscopy signals, in which F ′ = 1 , F ′ = 2 , and F ′ = 3 show the transition of F = 2 to F ′ = 1 , 2 , 3 , and CO12, CO13, CO23 mean the transition to 1–2, 1–3, and 2–3 crossover. The blue curve is the DAVLL signal.