QUANTUM CORRELATIONS AND FISHER INFORMATION IN MULTIPARTITE TWO-LEVEL SYSTEM UNDER KERR MEDIUM EFFECT

This paper investigates the evolution of global quantum discord (GQD) and quantum Fisher information (QFI) of the interaction of multiple two-level atomic systems (TLS) with a single thermal field mode and a non-linear Kerr medium (NLKM) considering the cases of intrinsic decoherence and its absence. Results indicate that increasing the number of atomic systems (N) while maintaining the NLKM parameter constant chi leads to higher GQD and QFI values for both intrinsic intrinsic decoherence cases. With rising chi, the GQD values decrease but the oscillation rate of the GQD increases. The presence of intrinsic decoherence does not significantly reduce the GQD quasi-static value compared to the no-decoherence scenario for certain chi values. At the same time, a different trend is observed for higher chi values. The average QFI value rises with reduced oscillation amplitudes for higher chi values and larger N subsystems. Unlike the GQD, higher chi values aid in maintaining average QFI in the presence of intrinsic decoherence. For moving TLS, changing chi does not alter the oscillation periods of the GQD and QFI. The GQD values decrease with increased chi in the moving system case, while the QFI improves with higher chi values. Additionally, higher average thermal photons within the system suppress the GQD and QFI values and decrease oscillation amplitudes for both quantifiers.