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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Quantum stabilization in anharmonic crystals.
Sergio Albeverio1, Yuri Kondratiev, Yuri Kozitsky
1Abteilung für Stochastic, Universität Bonn, D 53115 Bonn, Germany. albeverio@uni-bonn.de
Physical Review Letters
|June 6, 2003
Summary
Quantum effects stabilize interacting particles in crystalline fields, preventing phase transitions regardless of temperature. Stability depends on particle mass and tunneling frequency, not external conditions.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Statistical Mechanics
Background:
- Investigating the behavior of interacting quantum particles in crystalline fields is crucial for understanding material properties.
- Previous work has explored the influence of external fields on phase transitions in such systems.
- The role of quantum effects in stabilizing these systems against structural phase transitions requires further rigorous analysis.
Purpose of the Study:
- To describe a mechanism for stabilizing a model of interacting quantum particles in a double-well crystalline field using quantum effects.
- To establish a stability condition dependent on particle mass, interaction intensity, and crystalline field parameters.
- To rigorously determine the impact of quantum stabilization on the occurrence of structural phase transitions.
Main Methods:
- Modeling interacting quantum particles in a double-well crystalline potential.
- Deriving a stability condition based on quantum mechanical parameters.
- Analyzing the analyticity of free energy density with respect to external fields.
- Investigating the decay properties of displacement-displacement correlation functions.
Main Results:
- A stability condition is derived, independent of temperature, contingent on small particle mass and/or high tunneling frequency.
- Under the stability condition, the infinite-volume free energy density is analytic in the external field.
- The displacement-displacement correlation function exhibits exponential decay, precluding phase transitions at all temperatures.
Conclusions:
- Quantum effects provide a robust mechanism for stabilizing interacting particle systems in crystalline fields.
- Structural phase transitions are completely suppressed at all temperatures when the derived stability condition is met.
- This work offers a definitive answer to the influence of quantum mechanics on structural phase transitions in these models.
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