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1/f noise and very high spectral rigidity
A Relaño1, J Retamosa, E Faleiro
1Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, 28010 Madrid, Spain.
Summary
Spectral fluctuations in quantum systems resemble time series. This study reveals 1/f noise characterizes spectra with high rigidity, indicating a transition that suppresses fluctuations while maintaining scale-free correlations.
Area of Science:
- Quantum mechanics
- Statistical physics
- Complex systems
Background:
- Spectral fluctuations in quantum systems are analogous to time series.
- Power spectrum analysis reveals distinct behaviors for chaotic (1/f) and regular (1/f2) systems.
- This analogy links spectral rigidity to antipersistence.
Purpose of the Study:
- To investigate the relationship between spectral rigidity and correlation structure.
- To understand how increasing spectral rigidity affects spectral fluctuations.
- To identify characteristic fingerprints of spectral transitions.
Main Methods:
- Studied correlation structure of spectra with high spectral rigidity.
- Employed a family of random Hamiltonians to systematically increase spectral rigidity.
- Analyzed long-range correlations in the resulting spectra.
Main Results:
- A consistent 1/f power law was observed for the power spectrum across all studied spectra.
- This 1/f behavior persisted even as spectral fluctuations were significantly hindered.
- The scale-free correlation structure was preserved throughout the process.
Conclusions:
- 1/f noise is a key indicator of a transition in quantum systems.
- This transition suppresses spectral fluctuations while preserving scale-free correlations.
- The findings deepen the understanding of spectral rigidity and its impact on quantum system dynamics.
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