Numerical approach for the evolution of spin-boson systems and its application to the Buck–Sukumar model

Xue-Ying Liu,Xue-Zao Ren,Chen Wang,Xian-Long Gao,Ke-Lin Wang

Figure 3. Evolutions of (a) mean photon number $\langle \hat{n}\rangle $ and (b) atomic inversion $\langle {\hat{\sigma }}_{z}\rangle $ for P = 2000. (c) and (d) represent the same data for (a) and (b), respectively, but for P = 2000 and 3000 simultaneously. The BS model begins from a vacuum state $| t=0\rangle =| 0,e\rangle $ with ωf = ω0 = 1 and g− = g+=2ωf.