An estimation method based on the split-step quantum walk (SSQW) demonstrated that by adjusting a single parameter in the initial state, it is feasible to attain the quantum Crameŕ-Rao bound in multiparameter estimation. This parameter introduces a broad category of local initial states that function as optimized probes. Dissimilar to the ordinary quantum walk (OQW), SSQW does not necessitate entangled or parameter-dependent initial states. The analytical findings derived in this investigation show that SSQW outperform OQW in achievable precision of multiparameter estimation in nearly all possible scenarios. Furthermore, in single-parameter estimation, the additional parameter can be utilized to adjust the dynamics of the walk in such a manner as to enhance the precision of the estimation through maximizing the elements of the quantum Fisher information matrix. The results of this study indicate that SSQW can remarkably enhance the estimation schemes through its rich topological properties.

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• Quantum metrology
• Quantum parameter estimation
• Quantum walks