Semiclassical reproducibility of sawtooth structure observed for a periodically perturbed rounded-rectangular potential
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View abstract on PubMed
Summary
This summary is machine-generated.Tunneling probabilities in a periodically perturbed potential exhibit a sawtooth structure due to multi-quanta absorption. A semiclassical approach explains this phenomenon, revealing underlying mechanisms of quantum tunneling.
Area Of Science
- Quantum Mechanics
- Nonlinear Dynamics
- Condensed Matter Physics
Background
- Previous work identified a sawtoothlike structure in tunneling probabilities for periodically perturbed potentials.
- This structure arises from multi-quanta absorption tunneling and exhibits sudden changes due to harmonic channel replacements.
Purpose Of The Study
- To explore the underlying semiclassical mechanism responsible for the sawtooth structure in tunneling probabilities.
- To analyze the role of complex branches and semiclassical methods in reproducing the observed tunneling behavior.
Main Methods
- Application of semiclassical methods to analyze the sawtooth structure.
- Utilizing the Melnikov method to estimate the semiclassical weight and baseline of the tunneling probability.
- Analogy to Fourier decomposition using superposition of complex branches.
Main Results
- The semiclassical method successfully reproduces the overall sawtooth structure, with deviations in narrow transition regions.
- The baseline of the sawtooth structure is accurately described by the Melnikov method.
- The average tunneling probability exhibits an exponential dependence on perturbation amplitude (ε).
Conclusions
- Semiclassical analysis provides a robust framework for understanding the sawtooth tunneling phenomenon.
- The Melnikov method and superposition of complex branches are key to explaining the observed structure and its baseline.
- The study elucidates the intricate relationship between quantum tunneling, perturbation parameters, and semiclassical dynamics.
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