Universal Dynamical Control of Open Quantum Systems

Figure 20

Cooling and heating of a TLS by minimization (left: (a), (b), (c)) and maximization (right: (g), (h), (i)) of the change of linear entropy for a given bath spectrum (𝐺_𝑗, red) with 𝑗=1,2,3 denoting 𝑥, 𝑦, and 𝑧 components. The optimized system spectra (𝐹_𝑗, green) are shown for an energy constraint 𝐸=10² (left) and 𝐸=10³ (right) as contrasted to the unmodulated Hamiltonian 𝐻₀ (i.e., for 𝐸=0.001, 0.05, 0.1, …, 0.45, 0.499). All graphs are individually scaled to 1 with respect to their maximum value, and scaling of 𝜔 is the same as in Figure 18 (color online).