Surreal illustration of atomic magnetometers impact on science and technology.

Unlock the Invisible: How Atomic Magnetometers Are Revolutionizing Science

Lena Voss in Science & Nature August 2025 • 4 min read.

"From medical imaging to fundamental physics, explore how ultra-sensitive atomic magnetometers are pushing the boundaries of what we can detect and understand."

Imagine a device so sensitive it can detect the faintest magnetic whispers of the human brain or the subtle shifts in Earth's magnetic field caused by distant storms. Atomic magnetometers, particularly those operating without the need for super-cooling (non-cryogenic), are making this a reality. These devices boast spatial resolution and sensitivity rivaling even the most advanced superconducting quantum interference devices (SQUIDs), opening doors to applications previously deemed impossible.

The flexibility and extreme sensitivity of atomic magnetometers have already led to breakthroughs across numerous disciplines. In biomedicine, they're being used in magnetocardiography to map heart activity and magnetoencephalography to study brain function with greater precision than ever before. They're also contributing to inertial rotation sensing, enabling more accurate navigation systems, and even the measurement of fundamental physical constants, helping us refine our understanding of the universe.

One particularly exciting area of development involves hyperpolarized (HP) noble gases. These gases, with their enhanced magnetic properties, offer unique advantages in various applications, from nuclear physics experiments to magnetic resonance imaging (MRI). By combining atomic magnetometers with hyperpolarized noble gases, scientists can detect and manipulate these materials with unprecedented control, leading to discoveries that could reshape our understanding of the world around us.

What Makes Atomic Magnetometers So Powerful?

Surreal illustration of atomic magnetometers impact on science and technology.

The core principle behind these advanced magnetometers involves exploiting the quantum properties of atoms. Specifically, they often rely on alkali metals like cesium, potassium, or rubidium. When these atoms are exposed to a specific frequency of light (optical pumping), their electrons become spin-polarized, aligning their magnetic moments in a particular direction. This creates a highly sensitive system that can detect even the smallest changes in an external magnetic field.

The introduction of hyperpolarized noble gases further enhances the capabilities of atomic magnetometers. These gases, such as helium-3, xenon-129, or neon-21, have been specially treated to align the spins of their atomic nuclei, resulting in a significantly enhanced magnetic signal. When combined with the sensitive alkali metal vapor, the resulting system becomes an exceptionally powerful tool for detecting and manipulating these hyperpolarized gases.

Unparalleled Sensitivity: Detect magnetic fields with resolutions approaching the femtotesla range (10^-15 Tesla).
Non-Cryogenic Operation: Unlike SQUIDs, many atomic magnetometers function at or near room temperature, simplifying operation and reducing costs.
Versatility: Adaptable for use in a wide range of applications, from medical imaging to fundamental physics research.
Spatial Resolution: Offer high spatial resolution, allowing for precise mapping of magnetic fields.
Compatibility with Hyperpolarized Gases: Can be effectively combined with hyperpolarized noble gases to enhance signal detection and manipulation.

Recent research has focused on developing efficient methods to analyze the spin precessions of different hyperpolarized noble gases using atomic magnetometers. Spin precession refers to the way the magnetic moments of atoms wobble or rotate in response to an external magnetic field. By carefully studying these precessions, scientists can glean valuable information about the properties of the gases and the surrounding environment. One such approach involves system identification, a technique that allows researchers to model and predict the behavior of complex systems based on experimental data.

The Future of Magnetic Detection

As research continues, expect to see atomic magnetometers playing an increasingly vital role in diverse fields. Improved designs, enhanced sensitivity, and new applications are constantly emerging. From advancing our understanding of fundamental physics to revolutionizing medical diagnostics, the potential of these remarkable devices is only just beginning to be realized.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1109/jsen.2018.2873665, Alternate LINK

Title: Ultra-Sensitive Atomic Magnetometers For Studying Spin Precessions Of Hyperpolarized Noble Gases Based On System Identification

Subject: Electrical and Electronic Engineering

Journal: IEEE Sensors Journal

Publisher: Institute of Electrical and Electronics Engineers (IEEE)

Authors: Sheng Zou, Hong Zhang, Xiyuan Chen, Zhuo Wang, Wei Quan, Jian-Cheng Fang

Published: 2018-12-15

Everything You Need To Know

What are atomic magnetometers and what makes them so sensitive?

Atomic magnetometers are highly sensitive devices designed to detect subtle magnetic fields, even those as faint as the magnetic whispers of the human brain. Their sensitivity stems from exploiting the quantum properties of atoms, often using alkali metals like cesium, potassium, or rubidium. The core principle involves optical pumping, where atoms exposed to a specific frequency of light become spin-polarized, aligning their magnetic moments. This alignment creates a system capable of detecting minute changes in an external magnetic field, achieving resolutions approaching the femtotesla range.

How do atomic magnetometers compare to SQUIDs and what are the advantages?

Atomic magnetometers rival the sensitivity and spatial resolution of SQUIDs (Superconducting Quantum Interference Devices), but offer significant advantages. Unlike SQUIDs, many atomic magnetometers operate at or near room temperature, which simplifies their operation and reduces associated costs. This non-cryogenic operation eliminates the need for super-cooling, making them more practical for various applications, including medical imaging and field research where portability and ease of use are crucial.

In what ways are hyperpolarized noble gases utilized with atomic magnetometers, and what benefits do they provide?

Hyperpolarized (HP) noble gases, such as helium-3, xenon-129, or neon-21, are used with atomic magnetometers to enhance their capabilities. These gases have their atomic nuclei spins aligned, leading to a significantly enhanced magnetic signal. When combined with the sensitive alkali metal vapor within the atomic magnetometer, the system becomes exceptionally powerful for detecting and manipulating these hyperpolarized gases. This combination enables scientists to study these materials with unprecedented control, facilitating discoveries in areas such as nuclear physics and magnetic resonance imaging (MRI).

How are atomic magnetometers used in medical imaging, and what benefits do they bring to this field?

In biomedicine, atomic magnetometers are used in magnetocardiography and magnetoencephalography to study heart activity and brain function, respectively. These devices offer greater precision than traditional methods. They allow for more detailed mapping of magnetic fields, which can help diagnose conditions, gain insight into brain functions, and provide new avenues for medical breakthroughs.

What is spin precession and how is it analyzed using atomic magnetometers?

Spin precession refers to the way the magnetic moments of atoms wobble or rotate in response to an external magnetic field. Scientists use atomic magnetometers to study these precessions, extracting valuable information about the properties of gases and their surrounding environment. Through techniques like system identification, researchers can model and predict the behavior of complex systems based on experimental data derived from observing these spin precessions. This analysis is particularly valuable when studying hyperpolarized noble gases and understanding their interactions within different environments.