Dynamical decoupling noise spectroscopy

TL;DR

This paper presents a method using dynamical decoupling pulse sequences to accurately characterize the environmental noise spectral density, thereby improving strategies to mitigate decoherence in quantum systems.

Contribution

It introduces a technique to reconstruct the full environmental spectral density by comparing various pulse sequences, enhancing decoherence understanding and control.

Findings

Successfully reconstructs environmental spectral density

Distinguishes different contributions to decoherence

Provides a practical method for noise spectroscopy

Abstract

Decoherence is one of the most important obstacles that must be overcome in quantum information processing. It depends on the qubit-environment coupling strength, but also on the spectral composition of the noise generated by the environment. If the spectral density is known, fighting the effect of decoherence can be made more effective. Applying sequences of inversion pulses to the qubit system, we generate effective filter functions that probe the environmental spectral density. Comparing different pulse sequences, we recover the complete spectral density function and distinguish different contributions to the overall decoherence.