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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
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Hidden Phase of the Spin-Boson Model
Florian Otterpohl1,2, Peter Nalbach3, Michael Thorwart2,4
1Center for Computational Quantum Physics, Flatiron Institute, New York, New York 10010, USA.
Physical Review Letters
|September 30, 2022
Summary
Quantum systems in noisy environments exhibit complex behaviors. This study reveals a new aperiodic dynamics phase in quantum two-level systems coupled to sub-Ohmic baths, driven by bath oscillations.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Statistical mechanics
Background:
- Quantum two-level systems coupled to baths exhibit complex dynamics.
- Sub-Ohmic baths induce significant low-frequency quantum fluctuations.
- Non-equilibrium quantum dynamics can become highly non-Markovian.
Purpose of the Study:
- Investigate the phase diagram of polarization dynamics in a quantum two-level system.
- Identify novel phases beyond damped oscillations and overdamped decay.
- Characterize the behavior of quantum systems under strong coupling to sub-Ohmic baths.
Main Methods:
- Numerically exact time-evolving matrix product operator (TEMPO) approach.
- Analysis of quantum two-level system dynamics.
- Determination of phase boundaries in the parameter space.
Main Results:
- Identified a new phase characterized by aperiodic behavior at strong coupling.
- Mapped the phase diagram, including damped coherent oscillations, overdamped decay, and the new aperiodic phase.
- Demonstrated that the quantum two-state system dynamics are slaved to the oscillatory bath.
Conclusions:
- The interplay between quantum systems and sub-Ohmic baths leads to rich non-equilibrium dynamics.
- A novel aperiodic dynamics regime exists for strongly coupled quantum two-level systems.
- Bath oscillations play a crucial role in dictating the system's behavior.
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