Atom-chip trap for Rydberg atom experiments

We report on an atom-chip trap experiment designed to investigate the interactions between high-lying Rb Rydberg atoms (n$>$30) and the role of Rydberg atom impurities. A magnetic microtrap that can be transformed into a double-well potential is created by dc and rf currents running through microscopic wires on an atom chip. The two wells can be separated by several micrometers. The microtrap is loaded with ultracold Rb atoms from a mirror magneto-optical trap via an intermediate millimeter-size magnetic wire-trap. A home-built Rydberg excitation laser at $\sim $480 nm is used to excite Rydberg atoms in the magnetic trap.