Finite size cavity effect on nS rubidium Rydberg state lifetimes

Abstract

In this work, we present lifetime measurements of nS states of Rb as a function of the principal quantum number (40 n 70) using a sample of cold atoms held in a magneto-optical trap, which is performed in a finite size metal vacuum chamber. The Rydberg states are excited through a two-photon transition, and detected by pulsed field ionization. Our measurements are larger than the predictions by well established theoretical model (1984 Phys. Rev. A 30 2881 and 2009 Phys. Rev. A 79 052504). We have implemented a theoretical model, which considers the vacuum chamber as a lossy Fabry–Perot cavity with a discrete spectrum, and compared with experimental results. Such comparison indicates that the blackbody radiation contribution on Rydberg state lifetime can be decreased by using a small size metal cavity, without the need of cryogenic environment. This effect may have application in experiments where longer Rydberg lifetimes are required.

Measurements of blackbody radiation-induced transition rates between high-lying S, P and D Rydberg levels

“…Currently, we are unable to explore states with n > 110 because of the minimum residual electric fields we can achieve in a stable manner using field compensation. In principle, however, it should be possible to observe drastically reduced BBR-induced transition rates in a setup like ours [44].…”

“…We find that our experimental results deviate significantly from theoretical calculations [17][18][19][20][21][22] in welldefined ranges of n. We attribute these deviations to the spectral intensity distribution of the BBR within the apparatus [37][38][39][40][41][42][43]. Placing additional electrodes around the MOT leads to further changes in the observed transition rates, which indicates that under suitable conditions BBR-induced transitions could also be suppressed in our setup, thus increasing the lifetimes of the Rydberg states without the need for cooling down the apparatus [44]. This is confirmed by simple model calculations that take into account the additional electrodes.…”

Superatomic Rydberg State Excitation

“…Because the Rydberg state is extremely sensitive to the collision effect and extremely reactive, it has been widely studied in many fields, such as spectral analysis, quantum computing, and quantum information accuracy measurement. − Ordinary molecules (e.g., N 2 and O 2 ) that are applied to Rydberg state excitation (RSE) can cause different double-center interference effects and completely different ionization characteristics due to the shape and symmetry of molecular orbitals (MOs). , It is not easy to control the excitation of valence electrons to higher or specific Rydberg states for molecular RSE. , These results from the MOs of excited state in these molecules, especially the MOs of the low excited state, are too far from the atomic orbital properties. To date, it is still a great challenge to prepare and detect molecular Rydberg states. − Thus, developing a new system that can be used to achieve RSE is significant. Compared to normal molecules, superatoms as artificial molecular systems exhibit electronic structure properties similar to those of atoms.…”