Multiphoton catalysis is a non-Gaussian operation which has aroused interest recently in quantum information processing. There are two schemes of multiphoton catalysis in the current literature: one uses a beam splitter, while the other uses an optical parametric amplifier. We derive the catalysis operator in the Fock basis for each scheme and find a close relationship between them. We propose to enhance quantum entanglement of the two-mode squeezed vacuum state by performing two-mode multiphoton catalysis independently using two beam splitters. We calculate the optimal entanglement, which is maximized over two independent transmissivities, for the catalyzed states with various pairs of catalysis photon numbers, and find that in each case entanglement is enhanced only when the squeezing parameter is below a certain threshold. We also find that the optimal entanglement is nonzero in the limit of low squeezing, and deduce the analytical forms of the limiting catalyzed state and its entanglement in each case from numerical coefficients.

多光子催化是一种非高斯操作，最近引起了量子信息处理的兴趣。当前文献中有两种多光子催化方案：一种使用分束器，而另一种使用光学参量放大器。我们为每种方案在Fock基础上推导催化算子，并找到它们之间的密切关系。我们建议通过使用两个分束器独立执行双模多光子催化来增强双模压缩真空状态的量子纠缠。我们针对具有各种成对的催化光子数的催化态计算了最佳纠缠，该纠缠在两个独立的透射率上最大化，并且发现在每种情况下，仅当挤压参数低于某个阈值时纠缠才会增强。