1/f Fluctuations in the Dielectric Response of Triglycine Sulfate

1/f fluctuations have been observed in the imaginary part of the complex dielectric constant of ferroelectric triglycine sulfate crystals near the Curie temperature T c. The observed 1/f power spectral density S ε i (f) of the imaginary dielectric constant, when normalized to the square of the real part of the dielectric constant ε r, is given by S ε i (f)/ε r 2=3.2×10-15/f(Δ T) where Δ T=T-47.73(°C) in the paraelectric phase and Δ T=47.82-T(°C) in the ferroelectric phase.