Multipole Electrodynamic Ion Trap Geometries for Microparticle Confinement under Standard Ambient Temperature and Pressure Conditions

TL;DR

This paper demonstrates the design and testing of multipole linear Paul traps operating at standard ambient conditions, enabling stable microparticle confinement and ordered structure formation, with validated simulations and potential for larger particle numbers.

Contribution

It introduces new 8- and 12-electrode multipole trap geometries for microparticle trapping under SATP, expanding stability regions and enabling study of ordered structures.

Findings

Stable trapping regions are extended compared to quadrupole traps.

Ordered planar and volume microparticle structures emerge depending on parameters.

Experimental results agree well with stochastic Langevin simulations.

Abstract

Trapping of microparticles and aerosols is of great interest for physics and chemistry. We report microparticle trapping in multipole linear Paul trap geometries, operating under Standard Ambient Temperature and Pressure (SATP) conditions. An 8-electrode and a 12-electrode linear trap geometries have been designed and tested with an aim to achieve trapping for larger number of particles and to study microparticle dynamical stability in electrodynamic fields. We report emergence of planar and volume ordered structures of the microparticles, depending on the a.c. trapping frequency and particle specific charge ratio. The electric potential within the trap was mapped using the electrolytic tank method. Particle dynamics was simulated using a stochastic Langevin equation. We emphasize extended regions of stable trapping with respect to quadrupole traps, as well as good agreement between experiment and numerical simulations.