Quantum Leap in Navigation: Sandia’s Chip-scale Photonic Modulator Revolutionises Quantum Sensing

In a groundbreaking development that could reshape the future of navigation, scientists at Sandia National Laboratories have created a miniature silicon photonic modulator chip that brings us closer to a “quantum compass.” This innovative technology promises to provide ultra-precise navigation capabilities even in environments where GPS signals are unavailable or compromised, per Laser Focus World.

The Core of Quantum Navigation

At the heart of this advancement lies a technique called cold-atom interferometry, an ultra-precise method of measuring acceleration. Traditionally, atom interferometers were room-sized, making them impractical for widespread use. However, Sandia’s team, led by scientist Jongmin Lee, has dramatically reduced the size, weight, and power requirements of these systems.

The star of the show is a tiny photonic chip measuring just 8 millimetres on each side. This chip, adorned with Sandia’s green thunderbird logo, houses four single-sideband modulators with custom features. It serves as the heart of a laser system on a microchip, replacing a conventional laser system typically the size of a refrigerator.

Sandia National Laboratories’ Scientist Jongmin Lee (left) prepares a rubidium cold-atom cell for an atom interferometry experiment while Scientists Ashok Kodigala (right) and Michael Gehl initialize the controls for a packaged single-sideband modulator chip. (Photo: Laser Focus World)

Unprecedented Performance

What sets Sandia’s modulator apart is its ability to reduce unwanted echoes, known as sidebands, by an astonishing 47.8 decibels. This results in a nearly 100,000-fold drop in these disruptive signals, marking a significant improvement over existing technologies.

“We have drastically improved the performance compared to what’s out there,” says Ashok Kodigala, a member of the research team. This level of precision is crucial for the development of quantum inertial measurement units (IMUs) that could potentially minimise reliance on GPS satellites.

Bridging Research and Application

The development of this chip-scale photonic modulator represents a pivotal bridge between fundamental research and practical applications. It signifies a step towards enhancing the stability, fieldability, and commercial viability of atom interferometers.

Peter Schwindt, a quantum sensing scientist at Sandia, underscores the collaborative nature of this achievement: “We have colleagues with whom we can readily communicate and collaborate to address the critical challenges facing this technology for its field deployment.”

Cost-Effectiveness and Mass Production

One of the most formidable obstacles to the deployment of quantum navigation devices has been cost. A single full-sized commercial single-sideband modulator can incur an expense exceeding $10,000. Sandia’s innovation addresses this issue directly.

“We can manufacture hundreds of modulators on a single 8-inch wafer, and even more on a 12-inch wafer,” elucidates Ashok Kodigala. This capability to mass-produce these sophisticated components using conventional semiconductor manufacturing processes could substantially reduce the cost of quantum IMUs, thereby increasing their accessibility for diverse applications.

Beyond Navigation: Expanding Horizons

While the primary focus remains on navigation, the potential applications of this technology extend far beyond that domain. Researchers are investigating its utilisation in detecting subterranean cavities and resources by measuring minute variations in Earth’s gravitational force. The team also anticipates the potential of their optical components in LIDAR, quantum computing, and optical communications.

Looking Ahead

As the technology advances towards field deployment, anticipation grows regarding its profound impact. “I believe it is truly exciting,” asserts Ashok Kodigala. “We are making substantial progress in miniaturisation for a wide range of applications.”

The development of this chip-scale photonic modulator signifies a significant milestone in the pursuit of precise, GPS-independent navigation. It exemplifies the power of interdisciplinary collaboration and the potential of quantum technologies to revolutionise various domains. As we gaze into the future, Sandia’s innovation promises to unveil novel frontiers in navigation, sensing, and beyond, ushering in an era of unparalleled precision and reliability in motion sensing technology.