Figure 1

A contour plot of the work $W$ released by four three-level systems initially in the state ${\otimes }^4{\sigma }_p$ on the direct path exchange of the populations of levels $|1111⟩$ and $|0222⟩$. The levels of each system are $\{0,ϵ,ϵ\}$. Lighter regions correspond to more work extraction. The white lines separate regions of $l$-separability, the left-hand side being fully separable (SEP) and the rightmost region-genuinely multipartite entangled (GME). Notice that there are regions where work is extracted without generating any entanglement. However, as $W$ increases, $k$-partite entanglement starts appearing with $k$ progressively larger. The inset illustrates the direct quantitative relation between the amount of genuinely 4-partite entanglement measured by $\mathrm{GME}=E_{2^{N-1}-1}$ and the extractable work $W$ in the same setting and with $p_0=0.55$.Reuse & Permissions