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Intensity-field correlation of single-atom resonance fluorescence.
S Gerber1, D Rotter, L Slodicka
1Institute of Experimental Physics, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria.
Physical Review Letters
|June 13, 2009
Summary
Researchers measured the resonance fluorescence of a single barium ion (138Ba+). This revealed the atom
Area of Science:
- Atomic physics
- Quantum optics
- Single-atom manipulation
Background:
- Understanding the quantum nature of light-matter interactions is crucial.
- Single trapped ions provide a controllable system for studying fundamental quantum phenomena.
- Resonance fluorescence is a key observable in atomic spectroscopy.
Purpose of the Study:
- To directly measure the radiating dipole field of a single atom.
- To investigate the nonclassical behavior of resonance fluorescence.
- To probe the evolution of a single atom's quantum state after photon detection.
Main Methods:
- Utilized a single trapped 138Ba+ ion.
- Employed laser fields with well-defined phase for atom manipulation.
- Measured the intensity-field correlation function of resonance fluorescence.
- Conditional interference measurements based on photon detection.
Main Results:
- Recorded the regression of the resonance fluorescence source field.
- Demonstrated a direct measurement of the single-atom radiating dipole field.
- Observed strong nonclassical behavior in the measured correlation function.
Conclusions:
- The study provides direct evidence of nonclassical light generation by a single atom.
- Confirms the ability to probe and characterize single-atom quantum dynamics.
- Opens avenues for exploring quantum correlations and single-photon sources.
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