Loss rates for high-n, 49 ≲ n ≲ 150, 5sns (³S₁) Rydberg atoms excited in an ⁸⁴Sr Bose-Einstein condensate

Abstract

Measurements of the loss rates for strontium n 3 S1 Rydberg atoms excited in a dense Bose-Einstein condensate are presented for values of principal quantum number n in the range 49 n 150 and local atom densities of ∼1 to 3 × 1014 cm−3. Two main processes contribute to loss, associative ionization, and state changing. The relative importance of these two loss channels is investigated, and their n and density dependences are discussed using a model in which the Rydberg atom loss is presumed to involve a close collision between the Rydberg core ion and ground-state atoms. The present measurements are compared to earlier results obtained using rubidium Rydberg atoms. For both species the observed loss rates are sizable, ∼105 − 106 s−1, and limit the timescales over which measurements involving Rydberg atoms immersed in quantum degenerate gases can be conducted.