Fig. 7: Anti-flatness spectrum for a small subsystem.
The blue dots show (a) \({{{\rm{Tr}}}}{\rho }_{A}^{2}\), b \({{{\rm{Tr}}}}{\rho }_{A}^{3}\), and c the anti-flatness of the entanglement spectrum MA of all energy eigenstates below the spectral peak (positive temperature states) in the zero-momentum and reflection symmetric sector on a periodic nine-plaquette chain with \({j}_{\max }=1\), ag2 = 1.2 for subsystem length NA = 3. For comparison, the dashed red line shows the respective prediction for the reduced thermal density matrix ρA,th on the same chain.
