Temperature-driven nonclassical light

With reference to two well known scenarios, we discuss, for nonclassical light, the competition between quantum and thermal effects. It is seen that for nonclassical light to be produced some amount of temperature-induced disorder is needed plus quantum fluctuations of order $\hslash$ squared.

Figure 1

$\mathcal{Q}$ as a function of $\chi /\omega$ for several values of temperature, i.e., $t=0,0.25,0.5,0.75$.

Figure 2

Mandel parameter $\mathcal{Q}$ in the plane $\chi /\omega -t$. Note that for significantly negative $\mathcal{Q}$ values, like, for instance, $-0.06$, one definitely requires a finite temperature.

Figure 3

$\mathcal{Q}$ as a function of $t$ for several values of $\chi /\omega$, i.e., $\chi /\omega =0.02,0.05,0.1,0.2,0.5$. Negative Mandel factors demand finite temperatures.

Figure 4

Represents a zoom of $\mathcal{Q}$ as a function of $t$ of the bottom left corner of Fig. 3.

Figure 5

${\mathcal{Q}}_{\mathrm{JC}}$ as a function of $t$ for several values of $g/\omega$, i.e., $g/\omega =0$ to 2.

Figure 6

${\mathcal{Q}}_{\mathcal{JCK}}$ as a function of $t$ for $g/\omega =1.5$. $\chi /\omega$ ranges from 0.1 to 0.3.