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Updated: Mar 9, 2026
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Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
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Dynamical polarizability, screening and plasmons in one, two and three dimensional massive Dirac systems
Anmol Thakur1, Rashi Sachdeva2, Amit Agarwal1
1Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208016, India.
Summary
We analyzed charged massive Dirac particles to understand plasmon modes and electrostatic screening. Our findings reveal how screened potentials decay in different dimensions for massive and massless Dirac systems.
Area of Science:
- Condensed matter physics
- Quantum field theory
Background:
- Understanding the behavior of Dirac particles is crucial in condensed matter systems.
- The random phase approximation is a standard method for studying collective excitations.
Purpose of the Study:
- To derive analytical expressions for the dynamical polarization function of charged massive Dirac particles.
- To investigate the plasmon modes and electrostatic screening of Coulomb interactions.
- To analyze the dimensionality dependence of these phenomena.
Main Methods:
- Calculation of the density-density response function.
- Application of the random phase approximation (RPA).
- Derivation of analytical expressions for the polarization function in 1D, 2D, and 3D.
Main Results:
- For massive Dirac systems, screened potentials decay as r^-2 (2D), r^-3 (3D), and r^-1 (1D non-interacting).
- For massless Dirac systems, screened potentials decay as r^-3 (2D) and r^-4 (3D), with no screening in 1D.
- Analytical results for the polarization function are obtained across different dimensions.
Conclusions:
- The study provides a comprehensive analysis of electrostatic screening and plasmon dispersion for Dirac systems.
- The derived polarization functions are valuable for experimental and theoretical investigations of Dirac electrons.
- Dimensionality plays a critical role in the screening properties and potential decay of Dirac systems.
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