Noise Analysis for High-Fidelity Quantum Entangling Gates in an Anharmonic Linear Paul Trap

TL;DR

This paper analyzes noise sources affecting high-fidelity entangling gates in an anharmonic linear Paul trap, providing detailed noise mitigation strategies to achieve 99.9% fidelity in multi-ion quantum systems.

Contribution

It offers a comprehensive noise analysis and optimization framework for entangling gates in ion traps, advancing towards fault-tolerant quantum computing.

Findings

Identified key noise thresholds for 99.9% fidelity

Optimized segmented laser pulse protocols

Quantified control precision requirements

Abstract

The realization of high fidelity quantum gates in a multi-qubit system, with a typical target set at 99.9%, is a critical requirement for the implementation of fault-tolerant quantum computation. To reach this level of fidelity, one needs to carefully analyze the noises and imperfections in the experimental system and optimize the gate operations to mitigate their effects. Here, we consider one of the leading experimental systems for the fault-tolerant quantum computation, ions in an anharmonic linear Paul trap, and optimize entangling quantum gates using segmented laser pulses with the assistance of all the collective transverse phonon modes of the ion crystal. We present detailed analyses of the effects of various kinds of intrinsic experimental noises as well as errors from imperfect experimental controls. Through explicit calculations, we find the requirements on these relevant noise levels and control precisions to achieve the targeted high fidelity of 99.9% for the entangling quantum gates in a multi-ion crystal.