Stark spectroscopy of Rydberg atoms in an atom-ion hybrid trap

Abstract

We report on Rydberg spectroscopy of ultracold atoms in an atom-ion hybrid trap for probing the electric fields in a mixture of atoms and ions. We obtain spectra which exhibit excitation gaps corresponding to avoided level crossings in the Stark map. From these measurements we can conclude that the ground state atoms experience electrical fields of up to 250 V/cm. There is, however, a difficulty in interpreting the results, because some data indicate that the electrical fields are produced by the ions while other data indicate that they stem from the Paul trap. We discuss possible scenarios for explaining the measured data, provide first measurements to check these scenarios, and propose methods to finally solve this puzzle.

Trapped Rydberg ions: A new platform for quantum information processing

“…It may even be possible to engineer repulsive interactions between atoms and ions, that prevent Langevin collisions between the two and thus prevent so-called micromotion induced heating in hybrid atomion systems [204][205][206]. Recently, interactions between ultracold Rydberg atoms and trapped ions have been observed in experiments [207,208]. A different hybrid ion-atom system directly produced from an ultracold ensemble of Rb atoms was employed for the observation of a single-ion-induced Rydberg blockade effect for Rydberg atoms [209].…”

Long-Range Atom–Ion Rydberg Molecule: A Novel Molecular Binding Mechanism

“…Before we start our investigation of the long-range atom-ion Rydberg bound states we would like to mention, that in recent years there has been a growing interest in the collisions and interactions of cold atoms and ions (for reviews, see, e.g., [10,11]). As of late, also the interactions between ions and ultracold Rydberg atoms have been studied theoretically [12][13][14][15] as well as experimentally [16][17][18][19]. Building up on this, an observation of the proposed long-range atom-ion Rydberg molecule may be possible in the near future.…”

Observation of effects due to an atom's electric quadrupole polarizability

“…Alternatively the coupling to sidebands may be diminished by increasing Ω [24]. One could remove the sidebands entirely by modulating the Rydberg-excitation laser fields and microwave field such that these fields follow the oscillating Rydberg energy levels, or else one could confine ions using a rotating Paul trap [25], a Penning trap [26] or a digital ion trap [9,27] instead of an oscillating Paul trap.…”

“…Various experiments are emerging which involve highly-excited Rydberg states in strong quadrupole trapping fields: hybrid systems of neutral Rydberg atoms and trapped ions allow atom-ion interactions to be studied [8,9], Rydberg molecules can be sensitively detected using an ion trap [10], trapped Rydberg ions have recently shown potential for scalable quantum computing [11] and precision spectroscopy of Rydberg systems could be used to search for a fifth fundamental force [12]. The ion trap's electric fields cause extreme Stark effects in these systems [8,9,[13][14][15][16]; however, in this work we are concerned with the quadrupole effects that appear.…”