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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Optical Kerr effect and third harmonic generation in topological Dirac/Weyl semimetal
Optics Express
|December 28, 2019
Summary
Three-dimensional topological semimetals exhibit strong nonlinear optical properties in the terahertz range, comparable to graphene. These materials offer advantages for photonic and optoelectronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nonlinear Optics
Background:
- Topological semimetals host exotic quasiparticles like massless Dirac fermions.
- Understanding their nonlinear optical response is crucial for advanced photonic applications.
Purpose of the Study:
- To investigate the nonlinear optical response of 3D topological semimetals.
- To determine the potential of these materials as alternatives to graphene in nonlinear optics.
Main Methods:
- Quantum mechanical formalism to couple 3D Dirac fermions with multiple photons.
- Analytical derivation of third-order interband nonlinear optical conductivities.
Main Results:
- Massless Dirac fermions in 3D topological semimetals show strong terahertz nonlinearity.
- Kerr nonlinear refractive index and harmonic generation susceptibility are comparable to graphene.
- Achieved nonlinear optical coefficients are orders of magnitude stronger than many nonlinear crystals.
Conclusions:
- 3D topological semimetals are promising for nonlinear optics due to strong optical nonlinearity and material advantages.
- These materials offer greater design flexibility and ease of fabrication for photonic and optoelectronic devices compared to graphene.
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