Role of temperature in the occurrence of some Zeno phenomena

Temperature can be responsible for strengthening effective couplings between quantum states, determining a hierarchy of interactions, and making it possible to establish such dynamical regimes known as Zeno dynamics, wherein a strong coupling can hinder the effects of a weak one. The relevant physical mechanisms which connect the structure of a thermal state with the appearance of special dynamical regimes are analyzed in depth.

Figure 1

The upper atomic level (corresponding to the state $\left|1\right.〉$) is resonantly coupled to the intermediate level ($\left|2\right.〉$), which in turn is resonantly coupled to the lowest level ($\left|3\right.〉$).

Figure 2

The survival probability of the atomic state $\left|1\right.〉$ as a function of time, for different values of the relevant parameters. (a) ${\omega }_a/{\omega }_b=10$, $g_{12}/{\omega }_b=g_{23}/{\omega }_b=1$, for different values of the temperature: $T/{\omega }_b=0.1$ (red solid line), $T/{\omega }_b=1$ (green dotted line), $T/{\omega }_b=50$ (blue dashed line), $T/{\omega }_b=250$ (black bold line). (b) ${\omega }_a/{\omega }_b=50$, $g_{12}/{\omega }_b=g_{23}/{\omega }_b=1$, for different values of the temperature: $T/{\omega }_b=0.1$ (red solid line), $T/{\omega }_b=1$ (green dotted line), $T/{\omega }_b=250$ (blue dashed line), $T/{\omega }_b=1250$ (black bold line).

Figure 3

Survival probability of the atomic state $\left|1\right.〉$ at low and high temperatures. The relevant quantities are ${\omega }_b/{\omega }_a=10$, $g_{12}/{\omega }_a=1$, $g_{23}/g_{12}=6$; temperature: $T/{\omega }_a=0.1$ (red solid line), $T/{\omega }_a=250$ (black dashed line).