Influence of the nonlinearity of nondegenerate parametric amplifier cavity fields on quantum phenomena of two coupled qubitsA.-B. A. Mohamed, Hashim M. Alshehri, E. M. Khalil and S. Abdel-KhalekEur. Phys. J. Plus, 136 10 (2021) 1006DOI: https://doi.org/10.1140/epjp/s13360-021-01991-y