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Updated: Jul 9, 2026
09:38
Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Time-domain terahertz emission spectroscopy on van der Waals materials.
Claudia Gollner1,2, Aaron Lindenberg1,3, Tony F Heinz1,2
1Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 USA.
MRS Communications
|July 8, 2026
Summary
Time-domain terahertz emission spectroscopy precisely probes ultrafast charge carrier dynamics. This review highlights its application in van der Waals materials like graphene, advancing our understanding of these novel systems.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spectroscopy
Background:
- Time-domain terahertz (THz) emission spectroscopy directly measures transient photocurrents via emitted THz electric fields.
- Advances in ultrafast lasers and material science enhance THz emission spectroscopy's precision for charge carrier dynamics.
- THz emission spectroscopy is a versatile tool for studying ultrafast phenomena like hot carriers and Dirac fermions.
Purpose of the Study:
- To review time-domain THz emission spectroscopy as a method for probing ultrafast charge carrier dynamics.
- To explore the application of THz emission spectroscopy in bulk and 2D van der Waals materials.
- To highlight the potential of THz emission spectroscopy for understanding nonlinear material responses.
Main Methods:
- Experimental description of time-domain THz emission spectroscopy.
- Application of THz emission spectroscopy to bulk and 2D van der Waals materials.
- Focus on graphene and transition metal dichalcogenide layers.
Main Results:
- THz emission spectroscopy offers precise insights into charge carrier dynamics.
- The technique is applicable to various ultrafast processes in materials.
- Limited application of THz emission spectroscopy in van der Waals materials is noted.
Conclusions:
- Time-domain THz emission spectroscopy is a valuable complementary technique for studying ultrafast charge carrier dynamics.
- Further application in van der Waals materials, particularly 2D systems, is encouraged.
- The method provides insights into nonlinear responses and charge carrier behavior in novel materials.
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