While the world waits for quantum computing to mature, other quantum-based technologies may see nearer-term use in a variety of industrial applications. One of these technologies is quantum sensing, which relies on quantum mechanics at an atomic level to provide much more accurate measurements of environmental forces like gravity, motion, temperature, pressure, and electromagnetism, than any traditional sensor technology can.
SBQuantum, a Canadian start-up based in Sherbrooke, Quebec, is one of the companies working in this space, and has developed a quantum magnetometer. The company described it as using a diamond crystal that contains “four sensing axes in a very small volume at the atomic scale, and the amplitude and direction of its magnetic field measurements provides high accuracy with no blind spots. The device’s use of quantum effects also provides greater accuracy than existing technologies.”
SBQuantum’s quantum magnetometer will soon have a high-profile test of its capabilities via the U.S. National Geospatial-Intelligence Agency’s MagQuest Challenge, which aims to find better ways to measure and map the Earth’s constantly-changing electromagnetic field, also known as the World Magnetic Model (WMM). The ability to detect these changes is significant because of the electromagnetic field’s role in navigation for everything from planes to smartphones. As part of this multi-million-dollar competition, the company’s quantum magnetometer will be launched into space, likely in mid-2025, aboard a satellite from SBQuantum partner Spire Global.
David Roy-Guay, CEO and Co-Founder at SBQuantum, recently spoke via email with Fierce Electronics, and answered the following questions:
Fierce Electronics: What are existing approaches to measuring the Earth's magnetic field, and why is a quantum-enabled approach better?
David Roy-Guay: Existing approaches are based on the SWARM ESA [European Spave Agency] satellite constellation the size of a small bus. which uses a boom to get the magnetometers meters away from the satellite. They also rely on a vectorized total magnetic field intensity atomic vapor magnetometer. Our compact, power-efficient and diamond-based quantum vector magnetometer enables a pure quantum vector magnetometer operation, reducing drift, increasing compactness and fidelity. Further, our solution leverages a multi-sensor approach combined with machine learning compensation algorithms to minimize the satellite magnetic signature, and enables that in a much more compact 6U CubeSat [nanosatellite] platform.
FE: What are some of the key applications for quantum magnetometers?
DRG: Magnetometers are an enabler technology for navigation, telling where the magnetic North is to every navigation instrument, and for exploration in mining to identify faults of critical minerals in the ground, and in intelligence/reconnaissance missions on the field. We are leveraging the highly local nature of the diamond magnetometer and enhanced drift properties to improve magnetic interference compensation algorithms, which will allow highly accurate vector magnetic field measurements even from drone platforms used for exploration in mining. SBQ also builds arrays of vector magnetometers to generate 5x the number of magnetic maps and generate real-time interpretations of magnetic events. For example, objects can be tracked beyond walls and classified based on their magnetic signature to provide intelligence/surveillance insights on the field in a way other sensing technologies can’t.
FE: Are there any connections between quantum sensing and quantum computing, and does it rely on quantum computers in any way?
DRG: Although quantum sensing and computing have very different objectives, they rely fundamentally on the efficient initialization, control and readout of a quantum system. Hence, single qubit gates, advanced quantum control schemes such as pulse shaping are exploited for high accuracy and high sensitivity sensing. Although 2-qubit gates are difficult to perform in the diamond system, there has been demonstrations of entanglement at distance of such systems and to perform basic quantum computing calculations. Finally, some pulse sequences to cancel some quantum effects are used for sensing, such as Ramsey and spin-echo sequences. So there is a strong connection between the two although the final implementation and customers differ a lot.