Demonstration of a state-insensitive, compensated nanofiber trap

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Optics
• Nanophotonics

Background:

• Precise control of neutral atoms near surfaces is crucial for quantum technologies.
• Dielectric surfaces can introduce unwanted light shifts that perturb atomic properties.
• Optical trapping of atoms near nanostructures presents challenges in maintaining atomic coherence.

Purpose of the Study:

• To experimentally demonstrate an optical trap for single Cesium atoms at a specific distance from a dielectric nanofiber.
• To mitigate light shifts using magic wavelengths for improved atomic state control.
• To enable new applications in quantum optical networks and surface-based atomic spectroscopy.

Main Methods:

• Utilizing counterpropagating red- and blue-detuned laser beams to create an optical trap.
• Operating at magic wavelengths to cancel differential scalar light shifts and suppress vector shifts.
• Measuring the absorption linewidth of the Cesium 6S(1/2)→6P(3/2) transition.

Main Results:

• Single Cesium atoms were successfully localized approximately 215 nm from a dielectric nanofiber surface.
• Light shifts were significantly reduced by operating at magic wavelengths.
• An absorption linewidth of 5.7±0.1 MHz was measured, close to the free-space value.
• An optical depth of approximately 66 was achieved.

Conclusions:

• The experimental realization of this optical trap provides a robust method for controlling atoms near dielectric surfaces.
• This technique enhances capabilities for building functional quantum optical networks.
• It opens avenues for high-precision atomic spectroscopy in proximity to nanostructured materials.