Reduced QED with Few Planes and Fermion Gap Generation
Eduard V Gorbar1,2, Valery P Gusynin2, Maxim R Parymuda1
1Department of Physics, Taras Shevchenko National Kyiv University, 03022 Kyiv, Ukraine.
Entropy (Basel, Switzerland)
|September 28, 2023
Summary
Reduced quantum electrodynamics is generalized for layered heterostructures, formulating an effective gauge theory. This theory reveals enhanced screening in multi-layered systems, impacting critical coupling for gap generation in materials like graphene.
Area of Science:
- Condensed matter physics
- Quantum field theory
- Materials science
Background:
- Reduced quantum electrodynamics (QED) is extended to analyze few-atomically-thick heterostructures.
- A (2+1)-dimensional effective gauge theory is formulated for N-layered systems.
Purpose of the Study:
- To generalize reduced QED for N-layered heterostructures.
- To analyze screened electromagnetic interactions and dynamical gap generation.
Main Methods:
- Formulation of an effective (2+1)-dimensional gauge theory.
- Calculation of polarization functions for screened interactions.
- Study of dynamical gap generation using the massless Dirac equation.
Main Results:
- Explicit formulae for screened electromagnetic interaction in two- and three-layer systems.
- Demonstration that additional screening in a two-layer system increases the critical coupling constant for gap generation compared to graphene.
Conclusions:
- The generalized theory accurately describes multi-layered heterostructures.
- Layered screening significantly affects excitonic gap generation, offering insights for novel material design.
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