The paper states the shot-noise limited sensitivity as: δB(τ) = 1/(γC√(NT)). However, the standard expression includes the coherence time T₂ or T₂* in the denominator, not simply the coherent duration T. More critically, the subsequent text incorrectly defines the parameters: “T is derived from T₂ when employing the Ramsey measurement, whereas the Hahn-echo measurement necessitates deriving T from T₂.” This duplicates T₂ for both methods, which is erroneous, Ramsey fringe measures T₂* (typically microseconds), while Hahn echo measures T₂ (typically longer). This basic misidentification undermines all sensitivity calculations presented.
