When catalysis is useful for probabilistic entanglement transformation
Yuan Feng, Runyao Duan, Mingsheng Ying · Physical Review A · 2004
We determine all $2\ifmmode\times\else\texttimes\fi{}2$ quantum states that can serve as useful catalysts for a given probabilistic entanglement transformation, in the sense that they can increase the maximal transformation probability. When higher-dimensional catalysts are considered, a sufficient and necessary condition is derived under which a certain probabilistic transformation has useful catalysts.