US creates ‘mother of all motion sensors’ to battle GPS jamming in war zones

Scientists at Sandia National Laboratories have made a significant stride towards GPS-free navigation with a breakthrough in quantum sensing.

They have developed “the mother of all motion sensors” that is so precise that it could potentially lessen the US’ dependence on GPS.

It becomes a critical capability in scenarios where GPS is jammed or spoofed or in conflict zones where enemy forces can disrupt satellite signals.

“Accurate navigation becomes a challenge in real-world scenarios when GPS signals are unavailable,” said Sandia scientist Jongmin Lee.

Harnessing quantum mechanics

The scientists have successfully harnessed silicon photonic microchip components to perform atom interferometry. Atom interferometry is a quantum sensing technique that measures acceleration and angular velocity with exceptional accuracy.

“By harnessing the principles of quantum mechanics, these advanced sensors provide unparalleled accuracy in measuring acceleration and angular velocity, enabling precise navigation even in GPS-denied areas,” remarked Lee.

Traditionally, the sensors used for atom interferometers were large, often occupying entire rooms. The Sandia team has successfully miniaturized these components.

They have introduced a new high-performance silicon photonic modulator.

For context, modulators are devices used to control the properties of light, particularly its frequency. However, they often produce unwanted additional frequencies alongside the desired one. These extra frequencies are called “sidebands” and are analogous to echoes in sound.

“Sandia’s suppressed-carrier, single-sideband modulator reduces these sidebands by an unprecedented 47.8 decibels — a measure often used to describe sound intensity but also applicable to light intensity — resulting in a nearly 100,000-fold drop,” stated the researchers in the press release .

Reducing size, overcoming cost barriers

The new modulator, along with other advancements like a smaller vacuum chamber and a consolidated apparatus, contributes to reducing the size, weight, and power needs of these sensors .

“We have drastically improved the performance compared to what’s out there,” expressed Sandia scientist Ashok Kodigala.

Cost has long been a major hurdle in deploying quantum navigation devices. Notably, laser systems are essential for atom interferometers, and modulators are a key component of those laser systems.

“Just one full-size single-sideband modulator, a commercially available one, is more than $10,000,” Lee highlighted.

Sandia’s innovative approach involves miniaturizing components onto silicon photonic chips, effectively cutting costs.

“We can make hundreds of modulators on a single 8-inch wafer and even more on a 12-inch wafer,” commented Kodigala. These chips can be mass-produced using the same processes as computer chips, making them significantly more affordable and accessible.

Expanding applications

While navigation is a primary focus, this technology’s potential extends far beyond. It holds promise for locating underground cavities and resources, enhancing LIDAR systems, advancing quantum computing , and revolutionizing optical communications.

The Sandia team is actively exploring these diverse applications as they continue to make strides in miniaturization.

Their aim is to transform atom interferometers into a compact quantum compass, bridging the gap between basic research and commercial development.

“We’re making a lot of progress in miniaturization for a lot of different applications,” concluded Kodigala.

This achievement marks a crucial step towards developing a quantum compass capable of navigating even when GPS signals are unavailable.