2-Rényi CCNR negativity of compact boson for multiple disjoint intervals
摘要
We investigate mixed-state bipartite entanglement between multiple disjoint intervals using the computable cross-norm criterion (CCNR). We consider entanglement between a single interval and the union of remaining disjoint intervals, and compute 2-Rényi CCNR negativity for a 2d massless compact boson. The expression for 2-Rényi CCNR negativity is given in terms of cross-ratios and Riemann period matrices of Riemann surfaces involved in the calculation. In general, the Riemann surfaces involved in the calculation of n-Rényi CCNR negativity do not possess a Zn symmetry. We also evaluate the reflected Rényi entropy related to the 2-Rényi CCNR negativity. This reflected Rényi entropy is a universal quantity. We extend these calculations to the 2d massless Dirac fermions as well. Finally, the analytical results are checked against the numerical evaluations in the tight-binding model and are found to be in good agreement.