A Synchronous Spin-Exchange Optically Pumped NMR-Gyroscope

TL;DR

This paper introduces a synchronized spin-exchange NMR gyroscope that achieves high sensitivity and stability by suppressing systematic errors, advancing inertial navigation technology.

Contribution

It presents a novel NMR gyroscope design with error suppression techniques, improving measurement stability and sensitivity over previous models.

Findings

Rotation rate ARW sensitivity of 16 μHz/√Hz

Bias instability of approximately 800 nHz

Suppressed systematic errors from alkali-metal atoms

Abstract

Inertial navigation systems generally consist of timing, acceleration, and orientation measurement units. Although much progress has been made towards developing primary timing sources such as atomic clocks, acceleration and orientation measurement units often require calibration. Nuclear Magnetic Resonance (NMR) gyroscopes, which rely on continuous measurement of the simultaneous Larmor precession of two co-located polarized noble gases, can be configured to have scale factors that depend to first order only on fundamental constants. The noble gases are polarized by spin-exchange collisions with co-located optically pumped alkali-metal atoms. The alkali-metal atoms are also used to detect the phase of precession of the polarized noble gas nuclei. Here we present a version of an NMR gyroscope designed to suppress systematic errors from the alkali-metal atoms. We demonstrate rotation rate angle random walk (ARW) sensitivity of 16 $\mu \text{Hz}/\sqrt{\text{Hz}}$ and bias instability of $\sim$800 nHz.