Quantum speed limits of a qubit system interacting with a nonequilibrium environment
He Zhi†, , Yao Chun-Mei, Li Li, Wang Qiong
       

The non-Markovianity as a function of the ohmicity parameter s. Other parameters are λ = 0.3, Ω = 10, γ = 0.1, and D = 2, which is same to that of the Ref. [36].