Figure 7
From: Variational quantum metrology for multiparameter estimation under dephasing noise
Optimizing classical bound \(\textsf{C}_{\textsf{F}}\) through Variational Quantum Metrology. (a) Plot of the cost function \(\mathcal {C} (\varvec{\theta },\varvec{\mu }) = \textsf{C}_{\textsf{F}}\) versus the number of iterations across various noise probabilities \(\lambda\). (b) Plot of the corresponding optimal values of \(\mathsf {C'}_{\textsf{F}}\) and \(\mathsf {C'}_{\textsf{S}}\), and their counterparts extracted from Fig. 3a (in grayscale). These numerical results pertain to the star-graph configuration.
