# Synopsis: Something magic in the alkalis

Rubidium atoms trapped in optical lattices are shown to exhibit a magic-wavelength behavior.

The internal energy-level spacing of optically trapped atoms is generally affected by a differential Stark shift due to frequency-dependent polarizabilities. In an ensemble of traps of differing depths, this leads to inhomogeneous broadening in the atomic transitions—a rather annoying situation where an accurate control of these transitions is crucial. However, if the frequency of the trapping light is properly chosen, two levels of an atomic transition may experience identical Stark shifts. This is the basic idea of “magic wavelengths,” recently proposed in the context of metrology.

In a Rapid Communication published in Physical Review A, Nathan Lundblad from Bates College, Trey Porto from NIST and the University of Maryland, all in the US, and Malte Schlosser from Technische Universität in Darmstadt, Germany, show that the Stark shift cancellation is indeed achievable in an ultracold gas of ${}^{87}\text{Rb}$ atoms loaded into an optical lattice. In their experiment, they use a suitable light polarization together with an external magnetic field such that the scalar and vector Stark shifts of a microwave hyperfine transition nicely cancel with each other. Their results may have interesting implications in the development of precision measurements, atomic clocks, and quantum computing with neutral atoms. – Franco Dalfovo

### Announcements

More Announcements »

## Subject Areas

Atomic and Molecular Physics

## Previous Synopsis

Nonlinear Dynamics

Magnetism

## Related Articles

Optics

### Viewpoint: Ionization Delays That Stand Out

Attosecond-resolution experiments have determined the delay in an electron’s emission from a molecule after being ionized with light. Read More »

Atomic and Molecular Physics

### Focus: Giant Molecule Made from Two Atoms

Experiments confirm the existence of 1-micrometer-sized molecules made of two cesium atoms by showing that their binding energies agree with predictions.   Read More »

Atomic and Molecular Physics

### Focus: Choose the Number of Atoms in Your Cloud

A new technique allows researchers to specify the number of atoms in an ultracold cloud (in the millions) and then to reproduce that same number in repeated experiments. Read More »