Related Experiment Video
Updated: Feb 24, 2026
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
16.0K
Gate-Tunable Single Terahertz Meta-Atom Ultrastrong Light-Matter Coupling
Elsa Jöchl1, Anna-Lydia Vieli1, Lucy Hale1
1Institute of Quantum Electronics, ETH Zürich, Zürich 8093, Switzerland.
ACS Photonics
|February 23, 2026
Summary
Researchers demonstrate electrical control over light-matter interactions using a terahertz resonator and a 2D electron gas. This breakthrough enables tunable coupling strengths for novel electronic devices.
Area of Science:
- Condensed matter physics
- Quantum optics
- Terahertz spectroscopy
Background:
- Ultrastrong light-matter interactions are crucial for quantum technologies.
- Controlling these interactions with electrical fields is a significant challenge.
Purpose of the Study:
- To investigate the electrical tunability of light-matter interactions.
- To explore terahertz (THz) coupling between a complementary split ring resonator (cSRR) and a 2D electron gas (2DEG).
Main Methods:
- Transmission spectroscopy under a strong magnetic field.
- Electrical gate bias modulation to confine electrons to subwavelength dimensions (down to 410 nm).
Main Results:
- Landau polariton dispersion was found to be dependent on the applied electric bias.
- Demonstrated in situ tuning of normalized coupling strength (η) from 0.46 to 0.18.
- Excitation of standing plasma waves at zero magnetic field was achieved.
Conclusions:
- This study presents the first demonstration of THz far-field spectroscopy for electrically tunable interactions.
- The findings pave the way for novel tunable THz devices and fundamental studies of light-matter coupling.
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