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Self-energy correction to dynamic polaron responses.
1Physics Department, University of Antwerp, Universiteitsplein 1, 2060 Antwerpen, Belgium.
Summary
We calculated the self-energy correction for polaronic systems, finding that dynamical properties like effective mass and optical absorption are modified in first order due to screening effects.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Solid-state physics
Background:
- Polaronic systems exhibit complex interactions between electrons and lattice vibrations.
- Understanding these interactions is crucial for predicting material properties.
- Linear response theory is a standard tool for probing system dynamics.
Purpose of the Study:
- To present the first-order self-energy correction to linear response coefficients for polaronic systems.
- To investigate the impact of system-bath coupling on dynamical properties.
- To analyze the screening effects of the induced internal field.
Main Methods:
- Utilizing a truncated phase space approach.
- Applying first-order self-energy correction calculations.
- Analyzing the linear response coefficients of polaronic systems.
Main Results:
- The external perturbation induces a dynamically screening internal field.
- Mobility is affected to second order, while effective mass and optical absorption are modified to first order.
- The Fröhlich polaron model serves as a case study for the theoretical results.
Conclusions:
- The study highlights the significant first-order impact of self-energy corrections on key polaronic properties.
- Dynamical screening plays a crucial role in modifying effective mass and optical absorption.
- The truncated phase space approach provides a valuable framework for analyzing polaronic systems.
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