Surface trap with dc-tunable ion-electrode distance

TL;DR

This paper introduces a novel surface-electrode ion trap design that allows precise control of ion-electrode distance via dc voltages, enabling advanced quantum computing and noise detection applications.

Contribution

The paper presents a new trap architecture with dc-tunable ion-electrode distance, demonstrated with single calcium ions at variable heights, enhancing control and scalability.

Findings

Ion confinement at heights between 50 and 300 micrometers.

Successful cooling of motional modes into the ground state.

Potential for scalable quantum computing and noise detection.

Abstract

We describe the design, fabrication, and operation of a novel surface-electrode Paul trap that produces a radio-frequency-null along the axis perpendicular to the trap surface. This arrangement enables control of the vertical trapping potential and consequentially the ion-electrode distance via dc-electrodes only. We demonstrate confinement of single $^{40}$Ca$^+$ ions at heights between $50~\mu$m and $300~\mu$m above planar copper-coated aluminium electrodes. We investigate micromotion in the vertical direction and show cooling of both the planar and vertical motional modes into the ground state. This trap architecture provides a platform for precision electric-field noise detection, trapping of vertical ion strings without excess micromotion, and may have applications for scalable quantum computers with surface ion traps.