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Published on: December 4, 2017
Dynamical tunneling in macroscopic systems
1Department Physik, Arnold-Sommerfeld-Center for Theoretical Physics, and Center for Nanoscience, Ludwig-Maximilians-Universität, Theresienstrasse 37, 80333 München, Germany.
Physical Review Letters
|October 13, 2007
Summary
We studied macroscopic dynamical quantum tunneling (MDQT) in driven Duffing oscillators. We found conditions to observe MDQT, even when masked by thermal activation in nanomechanical and Josephson junction systems.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Nonlinear dynamics
Background:
- Macroscopic dynamical quantum tunneling (MDQT) is a quantum phenomenon relevant to Josephson junctions and nanomechanics.
- Driven nonlinear oscillators, like the Duffing oscillator, exhibit complex dynamics including coexisting stable states.
Purpose of the Study:
- To investigate MDQT in a driven Duffing oscillator under resonant conditions.
- To compare MDQT with driving-induced activation in macroscopic systems coupled to a heat bath.
- To identify experimental conditions for observing MDQT.
Main Methods:
- Theoretical calculation of tunneling rates in the driven Duffing oscillator.
- Analysis of the interplay between quantum tunneling and thermal activation.
- Comparison of theoretical predictions with experimental feasibility.
Main Results:
- The tunneling rate was calculated under resonant conditions between stable coexisting states.
- Driving-induced activation can mask MDQT in macroscopic systems coupled to a heat bath.
- Conditions for detecting MDQT with current experimental capabilities were identified.
Conclusions:
- MDQT in driven Duffing oscillators is theoretically investigated.
- A protocol for observing MDQT, distinct from thermal activation, is proposed.
- The findings are relevant for experiments in quantum physics and nanotechnology.
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