# Synopsis: Building a Better Atom Trap

An improved method for trapping cesium atoms near dielectric nanofibers raises possibilities for applications as well as tests of fundamental physics.

There are numerous techniques for trapping individual atoms or atom clouds in isolation, but one current goal is to find ways to trap atoms near structures. These composite systems could be used to make quantum networks that explore physical systems not available in the natural world. In Physical Review Letters, Akihisa Goban, at the California Institute of Technology in Pasadena, and collaborators demonstrate an improved technique for trapping a cesium atom approximately 200 nanometers from the surface of a dielectric nanofiber, in a way that is less disruptive to the atom than previous approaches.

Researchers have trapped cesium atoms near a dielectric nanostructure before, but Goban et al. enhance existing trapping schemes by two techniques. First, the laser fields that form the atom trap are all operated at so-called “magic frequencies” that minimize distortions between ground and excited electronic levels for a trapped atom. Second, two pairs of lasers, tuned to frequencies below and above an atomic transition, are configured to reduce differential trapping potentials among the various substates of ground and excited levels. These modifications avoid the light shifts that hindered previous implementations, thereby greatly reducing the inhomogeneous broadening for laser spectroscopy of the trapped atoms.

Goban et al.’s work brings various applications into the realm of possibility, including the creation of $1$D atomic mirrors for cavity QED, investigations of single-photon nonlinearities, and quantum many-body physics in $1$D spin chains. Additionally, the scheme might enable precision measurements of Casimir-Polder forces near dielectric surfaces. The trapping method can also be extended from trapping atoms near simple nanofibers to doing so near complex photonic crystal structures. – Daniel Ucko

More Features »

### Announcements

More Announcements »

## Subject Areas

Atomic and Molecular Physics

## Previous Synopsis

Atomic and Molecular Physics

Nuclear Physics

## Related Articles

Optics

### Viewpoint: A Multimode Dial for Interatomic Interactions

A tunable multimode optical cavity modifies interactions between atomic condensates trapped in its interior from long range to short range, paving the way towards exploring novel collective quantum phenomena. Read More »

Atomic and Molecular Physics

### Synopsis: Twisted Cavity Is a One-Way Light Path

A cavity containing spin-polarized atoms can serve as an optical isolator that breaks time-reversal symmetry by letting only forward-moving light pass.   Read More »

Atomic and Molecular Physics

### Synopsis: Nuclear Masses Don’t Add Up

The sum of the proton and deuteron masses minus the helium-3 nucleus mass, obtained from a measurement with a molecular ion, remains at odds with the number calculated from accepted values for these masses. Read More »