Entangled light via nonlinear vacuum-multiparticle interactions

We investigate the generation of a strongly entangled electromagnetic field through laser pumping a collection of $N$ two-level atoms in a two-mode optical resonator. The vacuum-multiparticle interactions enhance the coupling of the atomic sample to the cavity modes facilitating the creation of entangled photons at higher frequencies. In the dispersive atom-cavity limit, one can obtain a steady-state output field consisting of tens of such photons per mode.

Figure 1

(Color online) Mean number of entangled photons $\overline{N}$ as a function of $\delta ∕\kappa$ and $\Delta ∕2{\Omega }_0$. Here $\mid {\Delta }_1\mid \approx \mid {\Delta }_2\mid ={\Omega }_0$, $N{g}^2∕\kappa {\Omega }_0=3.2$, ${\gamma }_c∕\gamma =0.2$, and $N=100$.

Figure 2

Entanglement parameter $E$ as a function of $\Delta ∕2{\Omega }_0$ for $N{g}^2∕\kappa {\Omega }_0=3.2$, ${\gamma }_c∕\gamma =0.2$, $N=100$, $\mid {\Delta }_1\mid \approx \mid {\Delta }_2\mid ={\Omega }_0$, and $\delta ∕\kappa =-1$.