Materials challenges for trapped-ion quantum computers

Abstract

Trapped-ion quantum information processors store information in atomic ions maintained in position in free space by electric fields. Quantum logic is enacted through manipulation of the ions’ internal and shared motional quantum states using optical and microwave signals. Although trapped ions show great promise for quantum-enhanced computation, sensing and communication, materials research is needed to design traps that allow for improved performance by means of integration of system components, including optics and electronics for ion-qubit control, while minimizing the near-ubiquitous electric-field noise produced by trap-electrode surfaces. In this Review, we consider the materials requirements for such integrated systems, with a focus on problems that hinder current progress towards practical quantum computation. We give suggestions for how materials scientists and trapped-ion technologists can work together to develop materials-based integration and noise-mitigation strategies to enable the next generation of trapped-ion quantum computers. Trapped-ion qubits have great potential for quantum computation, but materials improvements are needed. This Review surveys materials opportunities to improve the performance of trapped-ion qubits, from understanding the surface science that leads to electric-field noise to developing methods for building ion traps with integrated optics and electronics.