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Updated: Sep 24, 2025
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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An ultrastrongly coupled single terahertz meta-atom
Shima Rajabali1, Sergej Markmann2, Elsa Jöchl2
1Institute of Quantum Electronics, ETH Zürich, 8093, Zürich, Switzerland. shimar@phys.ethz.ch.
Nature Communications
|May 9, 2022
Summary
We developed a new terahertz spectroscopy technique to study individual quantum systems. This method allows control over light-matter interactions at the single meta-atom and electron level.
Area of Science:
- Quantum optics
- Terahertz spectroscopy
- Metasurface optics
Background:
- Free-space coupling to subwavelength optical elements is crucial for controlling quantum systems.
- Characterizing individual quantum elements requires advanced spectroscopic techniques.
Purpose of the Study:
- To perform terahertz time-domain spectroscopy on individual, subwavelength meta-atoms.
- To investigate ultrastrongly coupled Landau polaritons at the single resonator level.
Main Methods:
- Utilizing an asymmetric immersion lens setup combined with a resonating metasurface.
- Performing terahertz time-domain spectroscopy on individual meta-atoms and electron gas samples.
Main Results:
- Unraveled linewidth dependence on meta-atom number, showing superradiant coupling quenching.
- Measured normalized coupling ratios of [Formula: see text] and [Formula: see text] for Landau polaritons and electron gas, respectively.
- Achieved a cooperativity of C=94 in a two-dimensional electron gas.
Conclusions:
- The developed technique enables control of ultrastrong light-matter interaction at the single resonator/electron level.
- This method is versatile for characterizing complex conductivity in micron-sized samples within the terahertz domain.
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