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Updated: Jul 2, 2025
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High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
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Interaction-Induced ac Stark Shift of Exciton-Polaron Resonances
T Uto1,2, B Evrard1, K Watanabe3
1Institute for Quantum Electronics, ETH Zürich, CH-8093 Zürich, Switzerland.
Physical Review Letters
|February 16, 2024
Summary
We demonstrate how laser-induced shifts in semiconductor MoSe2 can dramatically enhance interactions between optical excitations. This effect, driven by itinerant charges, significantly strengthens polaron interactions compared to bare excitons.
Area of Science:
- Condensed matter physics
- Quantum simulation
- Materials science
Background:
- The ac Stark effect is crucial for cold-atom physics and quantum simulation.
- Semiconductor heterostructures offer tunable electronic properties.
Purpose of the Study:
- To investigate the ac Stark effect in atomically thin MoSe2.
- To explore how itinerant charges modify interactions between optical excitations.
- To achieve a regime where background excitation interactions dominate the ac Stark shift.
Main Methods:
- Fabrication of a MoSe2-based heterostructure for charge tunability.
- Utilizing an intense pump laser with detuning from material resonances.
- Generating virtual collective excitations to study interactions.
Main Results:
- Achieved a regime where interactions with virtual excitations are the primary contributor to the ac Stark shift.
- Demonstrated that itinerant charges dramatically enhance interactions between optical excitations.
- Observed that attractive polaron interactions can be over an order of magnitude stronger than bare exciton interactions.
Conclusions:
- The ac Stark effect in tunable MoSe2 heterostructures provides a novel platform for studying light-matter interactions.
- Itinerant charges play a critical role in mediating and amplifying interactions between optical excitations.
- This work opens new avenues for analog quantum simulation using semiconductor systems.
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