AI Article Synopsis
- The concept of decoherence suggests that superposition states become mixed states due to interactions with the environment, relying on a specific set of preferred states (pointer states).
- A simple model illustrates that, even with moderate interactions between a system and its environment, these preferred states can form from the coherent dynamics of the entire system without needing thermal averaging.
- The research findings offer insights into decoherence and quantum thermalization, indicating that preferred states can adjust as system-environment coupling varies.
Article Abstract
The notion that decoherence rapidly reduces a superposition state to an incoherent mixture implicitly adopts a special representation, namely, the representation of preferred (pointer) states (PS). For weak or strong system-envrionment interaction, the behavior of PS is well known. Via a simple dynamical model that simulates a two-level system interacting with few other degrees of freedom as its environment, it is shown that even for intermediate system-environment coupling, approximate PS may still emerge from the coherent quantum dynamics of the whole system in the absence of any thermal averaging. The found PS can also continuously deform to expected limits for weak or strong system-environment coupling. Computational results are also qualitatively explained. The findings should be useful towards further understanding of decoherence and quantum thermalization processes.
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| http://dx.doi.org/10.1103/PhysRevLett.108.070403 | DOI Listing |
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