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Dynamical polarization, optical conductivity and plasmon mode of a linear triple component fermionic system
Bashab Dey1, Tarun Kanti Ghosh1
1Department of Physics, Indian Institute of Technology-Kanpur, Kanpur-208 016, India.
Summary
We explored the optical properties of linear triple component fermions, revealing unique responses due to a flat band. These findings differ significantly from Weyl fermions and free electron gases.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Fermionic Systems
Background:
- Linear triple component fermions are a pseudospin-1 generalization of Weyl fermions.
- These systems feature two linear bands and a flat band, influencing electronic properties.
Purpose of the Study:
- Investigate the density and optical responses of linear triple component fermions.
- Compare their behavior to Weyl fermions and 3D free electron gas.
Main Methods:
- Computation of dynamical polarization function.
- Calculation of random phase approximation dielectric function.
- Analysis of plasmon modes and optical conductivity.
Main Results:
- The flat band induces new particle-hole continuum regions and increases static polarization.
- A reduced plasmon gap, shifted absorption edge, and suppressed intercone transitions were observed.
- Plasmon dispersion follows the typical 3D system behavior: ω ~ ω₀ + ω₁q².
Conclusions:
- Linear triple component fermions exhibit distinct optical responses compared to Weyl fermions due to their flat band.
- These unique properties offer new avenues for exploring exotic electronic behaviors in quantum materials.
Keywords:
Weyl fermionsdynamical polarizationlinear response theorymultifold fermionsoptical conductivityplasmonstriple component fermionsMore Related Videos
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