Simultaneous and individual parameter estimation procedures for a two-twisting axis system

Abstract

We can utilize the Fisher quantum information matrix to evaluate the precision of any multiparametric forecasting methodology, due to the quantum Cramér–Rao bound. Using the density matrix vectorization approach, we examine both simultaneous and individual estimation procedures and the ratios of different estimation strategies. Our investigation takes into account interaction and intrinsic decoherence parameters, along with time, across various parameter combinations in a two-twisting axis model. Our findings suggest that using a simultaneous approach for multiple parameters in multiparameter estimation methods is generally more effective, offering higher precision than strategies that focus on individual parameters.