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Phase shift of a weak coherent beam induced by a single atom
Syed Abdullah Aljunid1, Meng Khoon Tey, Brenda Chng
1Center for Quantum Technologies and Department of Physics, National University of Singapore, 3 Science Drive 2, Singapore, 117543.
Physical Review Letters
|November 13, 2009
Summary
Researchers directly measured the phase shift caused by a single Rubidium-87 atom using a Mach-Zehnder interferometer. This experiment achieved a maximum phase shift of approximately 1 degree by tightly focusing the probe beam onto the atom.
Area of Science:
- Atomic physics
- Quantum optics
- Interferometry
Background:
- Single-atom interactions are crucial for quantum information processing.
- Measuring phase shifts induced by single atoms is challenging.
Purpose of the Study:
- To directly measure the phase shift imparted by a single Rubidium-87 atom.
- To investigate atom-light interactions in a Mach-Zehnder interferometer setup.
Main Methods:
- Utilized a Mach-Zehnder interferometer.
- Employed a tightly focused probe beam to interact with a single 87Rb atom.
- Measured the resulting phase shift on the coherent beam.
Main Results:
- Achieved a direct measurement of the phase shift.
- Observed a maximum phase shift of approximately 1 degree.
- Demonstrated strong focusing enhances atom-light interaction.
Conclusions:
- Single atoms can induce measurable phase shifts on light.
- The experimental method allows for precise study of atom-light interactions.
- This technique has potential applications in quantum sensing and metrology.
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