Bound He Rydberg states

Misha Ivanov

We discuss atomic stabilization in the process of resonance ionization via Rydberg states. We show that a strong resonance interaction between Rydberg states and a low-lying state substantially suppresses ionization. As a result, the population is trapped in the Rydberg states. Raman-type coupling of Rydberg states via the continuum is shown to be essential for the effect even when the bound-free interaction is weak.

S. Feneuille, P. Jacquinot

Georgios Doultsinos, Antonis Delakouras, David Petrosyan

We analytically derive the lower error bound for the preparation of any maximally entangled state of two atoms involving Rydberg-state interactions. This fundamental bound represents the minimum achievable error $E \geq ( 1 + π/2 ) Γ/B$ due to spontaneous decay $Γ$ of the Rydberg states and their finite interaction strength $B$, assuming that all other technical errors can be eliminated. Using quantum optimal control methods, we identify laser pulses for preparing a maximally entangled state of a pair of atomic qubits with an error only $1\%$ above the derived fundamental bound.

J P Connerade

N. J. van Druten, Harm Geert Muller

We study experimentally the behaviour of magnesium Rydberg series converging to the and ion states, coupled by a strong ( ) light field that is resonant with the transition between the ion states ( nm). This strong-field version of isolated-core excitation leads to modifications in the photoionization spectrum of the bound Rydberg series and to transitions between bound Rydberg states when the Rabi frequency associated with the core transition becomes larger than the Rydberg spacing.

William E. Cooke