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Updated: Feb 25, 2026
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Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
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Optical response in Weyl semimetal in model with gapped Dirac phase
S P Mukherjee1, J P Carbotte1,2
1Department of Physics and Astronomy, McMaster University, Hamiltion, Ontario, L8S 4M1, Canada.
Summary
This study explores optical properties in Weyl semimetals, revealing how scattering and broken time-reversal symmetry alter conductivity. The findings show significant changes in optical response near phase boundaries.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Optics
Background:
- Weyl semimetals (WSMs) exhibit unique electronic properties due to topologically protected Dirac cones.
- Understanding WSM optical properties is crucial for their application in advanced electronic devices.
- Time-reversal symmetry breaking and finite scattering rates can significantly modify WSM behavior.
Purpose of the Study:
- To investigate the optical properties of Weyl semimetals under broken time-reversal symmetry.
- To analyze the impact of a gap term (m) and Zeeman spin-splitting (b) on WSM optical conductivity.
- To examine the influence of finite residual scattering rates on these optical properties.
Main Methods:
- Theoretical modeling of Weyl semimetal optical properties.
- Application of the Kubo formalism for transport calculations.
- Analysis of AC and DC conductivity as a function of photon energy and temperature.
Main Results:
- AC conductivity retains quasilinear energy regions in the presence of scattering, though modified.
- The DC conductivity magnitude is altered and becomes inversely dependent on an effective Fermi velocity near phase boundaries.
- Leading corrections to conductivity at zero temperature and chemical potential exhibit quadratic dependence.
Conclusions:
- Finite gap terms, Zeeman splitting, and scattering rates significantly modify WSM optical response.
- The approach to the gapped Dirac semimetal phase boundary shows distinct conductivity behavior.
- These findings provide insights into the tunable optical properties of Weyl semimetals.
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