A versatile microwave source for cold atom experiments controlled by a field programmable gate array.

We present a microwave source that is controlled by a commercially available field-programmable gate array (FPGA). Using an FPGA allows for precise control of the time dependent microwave-dressing applied to a sample of trapped cold atoms. We test our microwave source by exciting Rabi oscillations in a Na spinor Bose-Einstein condensate.

A spinor Bose-Einstein condensate phase-sensitive amplifier for SU(1,1) interferometry.

The SU(1,1) interferometer was originally conceived as a Mach-Zehnder interferometer with the beam-splitters replaced by parametric amplifiers. The parametric amplifiers produce states with correlations that result in enhanced phase sensitivity. = 1 spinor Bose-Einstein condensates (BECs) can serve as the parametric amplifiers for an atomic version of such an interferometer by collisionally producing entangled pairs of | = 1, = ±1〉 atoms.

Atom-based vector microwave electrometry using rubidium Rydberg atoms in a vapor cell.

It is clearly important to pursue atomic standards for quantities like electromagnetic fields, time, length, and gravity. We have recently shown using Rydberg states that Rb atoms in a vapor cell can serve as a practical, compact standard for microwave electric field strength. Here we demonstrate for the first time that Rb atoms excited in a vapor cell can also be used for vector microwave electrometry by using Rydberg-atom electromagnetically induced transparency.

Spinor dynamics in an antiferromagnetic spin-1 thermal Bose gas.

We present experimental observations of coherent spin-population oscillations in a cold thermal, Bose gas of spin-1 23Na atoms. The population oscillations in a multi-spatial-mode thermal gas have the same behavior as those observed in a single-spatial-mode antiferromagnetic spinor Bose-Einstein condensate. We demonstrate this by showing that the two situations are described by the same dynamical equations, with a factor of 2 change in the spin-dependent interaction coefficient, which results from the change to particles with distinguishable momentum states in the thermal gas.

Field-programmable gate array based locking circuit for external cavity diode laser frequency stabilization.

We present a locking circuit for external cavity diode lasers implemented on a field-programmable gate array (FPGA). The main advantages over traditional non-FPGA-based locking circuits are rapid reconfigurability without any soldering and a friendly user interface. We characterize the lock quality by measuring the linewidth of a locked laser using electromagnetically induced transparency in a Rb vapor cell.