Faster Randomized Dynamical Decoupling

TL;DR

This paper introduces a randomized dynamical decoupling protocol that enhances error suppression in quantum systems with fewer pulses than traditional methods, outperforming existing deterministic sequences like Uhrig DD.

Contribution

The authors develop a probabilistic pulse sequence method that improves dynamical decoupling performance with minimal additional pulses, surpassing prior deterministic protocols.

Findings

Randomized protocol outperforms deterministic DD with fewer pulses.

The method effectively eliminates linear error terms in system-environment interactions.

Numerical simulations confirm the advantage of randomized over deterministic protocols.

Abstract

We present a randomized dynamical decoupling (DD) protocol that can improve the performance of any given deterministic DD, by using no more than two additional pulses. Our construction is implemented by probabilistically applying sequences of pulses, which, when combined, effectively eliminate the error terms that scale linearly with the system-environment coupling strength. As a result, we show that a randomized protocol using a few pulses can outperform deterministic DD protocols that require considerably more pulses. Furthermore, we prove that the randomized protocol provides an improvement compared to deterministic DD sequences that aim to reduce the error in the system's Hilbert space, such as Uhrig DD, which had been previously regarded to be optimal. To rigorously evaluate the performance, we introduce new analytical methods suitable for analyzing higher-order DD protocols that might be of independent interest. We also present numerical simulations confirming the significant advantage of using randomized protocols compared to widely used deterministic protocols.