Ion traps with enhanced optical and physical access

TL;DR

This paper introduces a novel rf ion trap design with significantly improved optical and physical access, enabling advanced quantum optics experiments and highly sensitive field sensing applications.

Contribution

The paper presents a new, simple rf ion trap geometry that offers up to 96% optical access, enhancing capabilities for quantum optics and sensing.

Findings

Achieved up to 96% optical access in the trap

Demonstrated potential for force sensing below 1 yN/Hz^{1/2}

Fabricated and characterized the novel trap geometry

Abstract

Small, controllable, highly accessible quantum systems can serve as probes at the single quantum level to study multiple physical effects, for example in quantum optics or for electric and magnetic field sensing. The applicability of trapped atomic ions as probes is highly dependent on the measurement situation at hand and thus calls for specialized traps. Previous approaches for ion traps with enhanced optical access included traps consisting of a single ring electrode or two opposing endcap electrodes. Other possibilities are planar trap geometries, which have been investigated for Penning traps and rf-trap arrays. By not having the electrodes lie in a common plane the optical access in the latter cases can be substantially increased. Here, we discuss the fabrication and experimental characterization of a novel radio-frequency (rf) ion trap geometry. It has a relatively simple structure and provides largely unrestricted optical and physical access to the ion, of up to 96% of the total 4pi solid angle in one of the three traps tested. We also discuss potential applications in quantum optics and field sensing. As a force sensor, we estimate sensitivity to forces smaller than 1 yN Hz^(-1/2).