Interactions between cold rubidium Rydberg atoms with external control

Georg A. Raithel

Duncan Tate, R.E. Wilson, Margaret S. Martei +1 more

We discuss our progress towards achieving external control of the electron temperature and the Coulomb coupling parameter of ultra-cold plasmas. Using a Littman dye laser, we create the plasma by partially photoionizing a dense, cold sample of rubidium atoms in a magneto-optical trap (MOT). At a controllable time delay, we excite neutral atoms in the plasma to a specific Rydberg state using a narrow bandwidth pulsed laser. We have made very qualitative measurements of the electron temperature as a function of delay from the exciting laser pulses. Some of our results suggest that the plasma is stabilized by the presence of the Rydberg atoms, with a longer lifetime and slower expansion rate than a plasma that evolves directly from a dense Rydberg sample.

Roy O. Wilson, Duncan Tate, Hakeem M. Oluseyi

We discuss our progress towards achieving external control of the electron temperature and the Coulomb coupling parameter of ultra‐cold plasmas. Using a Littman dye laser, we create the plasma by partially photoionizing a dense, cold sample of rubidium atoms in a magneto‐optical trap (MOT). At a controllable time delay, we excite neutral atoms in the plasma to a specific Rydberg state using a narrow bandwidth pulsed laser. We have made very qualitative measurements of the electron temperature as a function of delay from the exciting laser pulses. Some of our results suggest that the plasma is stabilized by the presence of the Rydberg atoms, with a longer lifetime and slower expansion rate than a plasma that evolves directly from a dense Rydberg sample.

Jennifer Elizabeth Robinson

I. I. Ryabtsev, Denis B. Tretyakov, Ilya I. Beterov +1 more

Cold atoms in highly excited Rydberg states are promising candidates to implement quantum logic gates of a quantum computer via long-range dipole-dipole interaction. Two-qubit gates require a controlled interaction of only two close Rydberg atoms. We report on the first spectroscopic observation of the resonant dipole-dipole interaction between two cold rubidium Rydberg atoms confined in a small laser excitation volume. The interaction strength was controlled by fine-tuning of the Rydberg levels into a Förster resonance using the Stark effect. The observed resonance line shapes are in good agreement with numerical Monte Carlo simulations.

Kashif Ammar Yasir, Wu-Ming Liu