Exact results for the entanglement across defects in critical chains (Q2882683)

The authors recapitulate fermionic results. Then, they study the oscillator chain and its RDM spectrum. The fermionic and bosonic Rényi entropies in terms of the single-particle eigenvalues are calculated and the resulting functions are given. The authors show how one can treat the bosonic case in complete analogy to the fermionic one. They prove that not only the von Neumann entropy, but also the Rényi entropies can be calculated asymptotically in closed form for all integer \(n\). Also, they sum up their findings. Lastly, a derivation of the bosonic spectrum from the transfer matrix of a two-dimensional Gaussian model are presented.