Ion-kinetic-energy sampling in a 22-pole trap using ring-electrode evaporation

Abstract

We present an experimental method for the characterization of the kinetic energies of ions confined in a 22-pole radio frequency trap by inducing a small potential barrier using the surrounding ring electrodes, allowing the selective extraction of ions. Energy sampling experiments have been performed on buffer gas thermalized He${}^{+}$ ions at trap temperatures between 10-180 K, resulting in distinct extraction curves as a function of the potential barrier, and a differentiated behavior depending on the escape time from the trap. The experiments are complemented by Monte Carlo simulations of the ion trajectories inside the calculated trap potential and allow us to investigate the properties of the sampling method, the role of ion motion coupling, and the impact of residual buffer gas collisions on the observed results. The technique has also been successfully applied to identify energetic H${}_3^{+}$ ions produced in an exothermic reaction inside the trap. Upon calibration, this method can provide relative kinetic energy distributions or be used to filter the maximum desired kinetic energy of the ions inside the trap.

References in corpus (12)

• Power-Law Distributions for a Trapped Ion Interacting with a Classical Buffer Gas
• Evaporative Cooling of Antiprotons to Cryogenic Temperatures
• Single atoms in a standing-wave dipole trap
• Characteristics of a magneto-optical trap of molecules
• Buffer-gas cooling of a single ion in a multipole radio frequency trap beyond the critical mass ratio
• Leak-out Spectroscopy, a universal method of action spectroscopy in cold ion traps
• Incomplete rotational cooling in a 22-pole ion trap
• Prospects of reaching the quantum regime in Li-Yb${}^{+}$ mixtures
• Dynamics of a single trapped ion immersed in a buffer gas
• Spectroscopy and ion thermometry of C${}_2^{-}$ using laser-cooling transitions
• Cold CAS Ion Trap -- 22 pole trap with ring electrodes for astrochemistry
• Buffer gas cooling of ions in time-dependent traps using ultracold atoms