Fraunhofer IAF, the Freiburg-based Fraunhofer Institute for Applied Solid State Physics, is showing the latest version of its diamond-based quantum magnetometer at World of Quantum 2025 in Munich, running June 24 to 27. The vector magnetometer uses nitrogen-vacancy (NV) centers in diamond to detect magnetic fields with a sensitivity the institute describes as "a few picotesla" and a high dynamic range.
The headline number is size. Fraunhofer IAF researchers cut the sensor head's footprint by a factor of 30 over the past year, bringing it down to roughly the size of conventional optically pumped magnetometers (OPMs) already used in industry, while keeping picotesla-range sensitivity. The institute wants to shrink the package by another factor of five next year and push sensitivity into the sub-picotesla range, according to Dr. Michael Stoebe, Business Unit Manager for Quantum Devices at Fraunhofer IAF.
Engineers who need vector field data without heavy calibration overhead will care about the diamond itself. The sensor uses <100>-oriented diamond, in which NV centers sit along all four crystal axes, so a single chip captures every vector component of a magnetic field at once. Conventional magnetometers typically need more setup to get the same result, and Fraunhofer IAF says this cuts calibration effort considerably.
The system also has optional water cooling, which the institute says keeps measurements stable under harsher operating conditions. Fraunhofer IAF grows its own NV-doped synthetic diamond for the sensor head and plans to move production from two-inch to four-inch, "industrially scalable" wafers next year, a step toward higher-volume manufacturing of the sensor cores, said Dr. Michael Kunzer, project manager at Fraunhofer IAF.
Fraunhofer IAF is targeting four application areas: biomedicine, materials testing, navigation, and geology. For navigation, the sensor can map regional variations in Earth's magnetic field to provide positioning without GNSS, a method that keeps working underwater, underground, in tunnels, or inside buildings where satellite signals don't reach. In geology, the same magnetic-mapping approach can locate underground mineral deposits and detect unexploded ordnance over large areas without contact, producing maps that estimate an object's depth, shape, and size.
The institute will demonstrate the prototype in Hall A1, Booth 439-3, on the show's "Quantum Future Boulevard," alongside a stated plan to keep shrinking the sensor generation by generation rather than treat this version as finished.
