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Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
Distribution of resonance widths and dynamics of continuum coupling
G L Celardo1, N Auerbach, F M Izrailev
1Dipartimento di Matematica e Fisica, Università Cattolica, Brescia, Italy.
Physical Review Letters
|March 17, 2011
Summary
We analyzed resonance widths in Fermi systems, finding deviations from standard distributions due to continuum coupling. This impacts understanding nuclear neutron resonances and chaotic dynamics.
Area of Science:
- Nuclear physics
- Quantum mechanics
- Statistical physics
Background:
- Resonance widths in many-body Fermi systems with open decay channels typically follow a chi-square (Porter-Thomas) distribution.
- Understanding deviations from this standard distribution is crucial for interpreting experimental data, particularly for neutron resonances in nuclei.
Purpose of the Study:
- To investigate the statistical properties of resonance widths in many-body Fermi systems.
- To analyze how continuum coupling strength and intrinsic system dynamics influence width distributions.
- To explore the emergence of deviations from the Porter-Thomas distribution and the potential for superradiance phase transitions.
Main Methods:
- Statistical analysis of resonance widths.
- Theoretical modeling of many-body Fermi systems with open decay channels.
- Examination of the impact of continuum coupling and intrinsic dynamics (chaotic vs. regular) on width distributions.
Main Results:
- Observed significant deviations from the standard chi-square (Porter-Thomas) width distribution.
- Demonstrated that deviations increase with the strength of continuum coupling.
- Identified that the interaction of intrinsic states through common decay channels drives these deviations, leading to a superradiance phase transition in the limit of perfect coupling.
- Showed that the width distribution is also dependent on the intrinsic dynamics of the system (chaotic or regular).
Conclusions:
- The standard Porter-Thomas distribution for resonance widths is not universally applicable in many-body Fermi systems with open decay channels.
- Continuum coupling plays a critical role in modifying resonance width statistics, potentially leading to novel phenomena like superradiance.
- The findings provide a theoretical framework for interpreting experimental data on neutron resonance width distributions in nuclei.
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