Trapped-ion quantum logic with global radiation fields

TL;DR

This paper introduces a novel trapped-ion quantum computing approach that eliminates the need for numerous radiation fields by using individually controlled voltages, enabling scalable quantum gates with high fidelity.

Contribution

The authors propose a new method for trapped-ion quantum computing that replaces multiple radiation fields with voltage-controlled gates, significantly improving scalability.

Findings

Implemented a versatile quantum gate with long-wavelength radiation.

Generated a maximally entangled state of two qubits with 98.5% fidelity.

Demonstrated potential applications in quantum metrology and sensing.

Abstract

Trapped ions are a promising tool for building a large-scale quantum computer. However, the number of required radiation fields for the realisation of quantum gates in any proposed ion-based architecture scales with the number of ions within the quantum computer, posing a major obstacle when imagining a device with millions of ions. Here we present a fundamentally different concept for trapped-ion quantum computing where this detrimental scaling entirely vanishes, replacing millions of radiation fields with only a handful of fields. The method is based on individually controlled voltages applied to each logic gate location to facilitate the actual gate operation analogous to a traditional transistor architecture within a classical computer processor. To demonstrate the key principle of this approach we implement a versatile quantum gate method based on long-wavelength radiation and use this method to generate a maximally entangled state of two quantum engineered clock-qubits with fidelity 0.985(12). This quantum gate also constitutes a simple-to-implement tool for quantum metrology, sensing and simulation.