Two mode coupling in a single ion oscillator via parametric resonance

TL;DR

This paper introduces a novel electric field-based method to couple two motional modes of a single trapped ion, enabling ground state cooling and heating rate measurement without optical access, with potential for quantum amplification.

Contribution

The paper presents a new technique for mode coupling in trapped ions using electric fields, reducing experimental complexity and enabling advanced quantum control.

Findings

Successfully coupled two motional modes via electric fields.

Achieved ground state cooling of a motional mode.

Measured the heating rate of the mode.

Abstract

Atomic ions, confined in radio-frequency Paul ion traps, are a promising candidate to host a future quantum information processor. In this letter, we demonstrate a method to couple two motional modes of a single trapped ion, where the coupling mechanism is based on applying electric fields rather than coupling the ion's motion to a light field. This reduces the design constraints on the experimental apparatus considerably. As an application of this mechanism, we cool a motional mode close to its ground state without accessing it optically. As a next step, we apply this technique to measure the mode's heating rate, a crucial parameter determining the trap quality. In principle, this method can be used to realize a two-mode quantum parametric amplifier.