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Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
15.3K
Quantum light drives electrons strongly at metal needle tips.
Jonas Heimerl1, Andrei Rasputnyi1,2, Jonathan Pölloth1
1Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
Nature Physics
|December 15, 2025
Summary
Bright squeezed vacuum, a quantum light state, drives photoemitted electrons, revealing attosecond dynamics. Post-selection on photon number is key to observing strong-field physics signatures like the high-energy plateau.
Area of Science:
- Quantum Optics
- Strong-Field Physics
- Attosecond Science
Background:
- Attosecond science uses intense laser pulses (coherent states) to drive photoemitted electrons.
- Bright squeezed vacuum is an intense quantum light state with a zero mean electric field.
- The potential for quantum light states to drive strong-field physics remains an open question.
Purpose of the Study:
- Investigate if bright squeezed vacuum can induce attosecond dynamics in photoemission.
- Explore the mechanism by which quantum light states manifest strong-field physics signatures.
Main Methods:
- Driving a needle tip with bright squeezed vacuum.
- Measuring photoemitted electron energy spectra.
- Post-selecting spectra based on individual photon number per pulse.
Main Results:
- Observed signatures of strong-field physics (high-energy plateau, cut-off) when post-selecting on photon number.
- Averaging over shots resulted in broad spectra lacking the plateau.
- This indicates electrons behave as if driven by an ensemble of coherent states.
Conclusions:
- Bright squeezed vacuum can generate attosecond dynamics signatures under specific conditions (photon number post-selection).
- Findings bridge quantum optics and strong-field physics, offering insights into quantum light behavior.
- Suggests potential for using driven electrons as quantum light sensors.
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