Fig. 2

Steady-state entanglement (logarithmic negativity). Entanglement between the cavity modes, panel (a), is always accompanied by considerable light–bacteria entanglement, panel (b), and for stronger couplings also by entanglement between the bacterial modes, panel (c). In all cases, base coupling strengths are varied as \(\tilde G_{\mathrm{I}} = [0,0.2]10^{15}\,{\mathrm{Hz}}\) (horizontal axis) and \(\tilde G_{{\mathrm{II}}} = 0\) (red lines), 0.05 (green lines), 0.1 (blue lines), 0.15 (magenta lines), and 0.2 (black lines) in 10¹⁵ Hz. We have also indicated the experimentally realised coupling strength \(\tilde G_{\mathrm{I}} = 3.9 \times 10^{13}\,{\mathrm{Hz}}\) from ref. ¹² and the corresponding \(\tilde G_{{\mathrm{II}}} = 6 \times 10^{13}\,{\mathrm{Hz}}\) as black dots