Efficient numerical method to calculate the three-tangle of mixed states
Kun Cao, Zheng-Wei Zhou, Guang‐Can Guo, Lixin He · Physical Review A · 2010
We demonstrate an efficient numerical method to calculate the three-tangle of general mixed states. We construct an ``energy function'' (target function) for the three-tangle of the mixed state under certain constraints. The energy function (target function) is then optimized via the replica exchange Monte Carlo method. We have extensively tested the method for the examples with known analytical results, showing remarkable agreement. The method can be applied to other optimization problems in quantum information theory.