Precision Quantum Parameter Inference with Continuous Observation

TL;DR

This paper introduces a novel quantum parameter estimation method using continuous measurements, allowing high-precision inference from a single quantum trajectory, reducing resource requirements compared to traditional approaches.

Contribution

The work presents a new continuous measurement-based quantum parameter estimation technique that achieves accurate results with minimal samples, unlike conventional methods.

Findings

Effective parameter estimation from a single quantum trajectory

Application to force sensing of a levitated nanoparticle

Reduced experimental resources needed for high-precision QPE

Abstract

Quantum Parameter Estimation (QPE) is important from the perspective of both fundamental quantum research and various practical applications of quantum technologies such as for developing optimal quantum control strategies. Standard and traditional methods for QPE involve projective measurements on thousands of identically prepared quantum systems. However, these methods face limitations, particularly in terms of the required number of samples and the associated experimental resources. In this work, we present a novel method for precise QPE that diverges from conventional techniques, employs continuous measurements, and enables accurate QPE with a single quantum trajectory. In an application, we demonstrate the use of the method for the task of parameter estimation and force sensing of a levitated nanoparticle.