In IHB case, heat currents Q_a and Q_b as a function of temperature T₁ in panel (a) and Q_a as a function of T₁ for different values of energy detuning Δ Ω in panel (b), various values of coupling strength ξ in panel (c) and diverse values of temperature T₂ in panel (d). We set Δ Ω = 2 γ in panels (a), (c), and (d), ξ = 2 γ in panels (a), (b), and (d) and T 2 = 20 γ in panels (a), (b), and (c). Other parameters are set to be γ A a = γ A b = γ B a = γ B b = γ and Ω m = 20 γ .