Fig. 5: Theoretical interpretation of enhanced decoherence rates via noise spectral analysis.
From: Critical fluctuations and noise spectra in two-dimensional Fe3GeTe2 magnets
a Red lines: temperature-dependent magnetic noise spectral density S(ω) of spin fluctuations; blue line: filter function Wt(ω) of the Hahn-echo pulse sequence. b Contour maps of parameter \({{{\mathcal{A}}}}\) versus Γ and ω0 for \({{{\mathcal{A}}}}\) = 0.1, 0.5, and 1. Red arrows denote parameter evolution driven by increasing distance d and approaching Tc, respectively. The blue point corresponds to the experiment results, and the black dashed line marks the condition Γ = ω0, dividing the parameter space into two regimes: Γ > ω0 and Γ < ω0. c Fitted Γ (see Eq. (6)) versus (T − Tc)/Tc measured from multiple samples. d Double-logarithmic representation of (c); Arrow marks the crossover from white-noise plateau to 1/f-slope region.
