He-McKellar-Wilkens topological phase in atom interferometry

Area of Science:

• Quantum mechanics
• Atomic physics
• Condensed matter physics

Background:

• The He-McKellar-Wilkens phase is a predicted topological phase related to the Aharonov-Casher effect via electric-magnetic duality.
• This phase arises from the interaction of an electric dipole with a magnetic field.

Purpose of the Study:

• To experimentally verify the existence and measure the magnitude of the He-McKellar-Wilkens phase.
• To compare experimental results with theoretical predictions.

Main Methods:

• Utilized a highly sensitive atom interferometer with spatially separated arms.
• Employed symmetry reversals, including electric and magnetic field direction changes.
• Measured a maximum phase shift of 27 mrad.

Main Results:

• The experiment successfully detected the He-McKellar-Wilkens phase.
• The measured phase value deviated by 31% from the theoretically predicted value.
• The deviation suggests the presence of uncontrolled systematic errors.

Conclusions:

• The experimental test provides evidence for the He-McKellar-Wilkens phase.
• Further investigation is needed to identify and mitigate systematic errors for more precise measurements.