Diamond sensor picks up the heart's magnetic signals ⚡ экспресс
Direct contactless detection of magnetic signals from the human heart has been demonstrated using quantum sensors based on NV centers in diamond. Three configurations were used to record magnetocardiograms in both shielded and unshielded environments, with signals averaged over hundreds to thousands of heartbeats. The compact, room-temperature sensors achieve a sensitivity of 6–26 pT/√Hz in an active volume below 0.5 mm³, defining the measurement performance. Although averaging is currently required, these figures already indicate the potential to detect single cardiac cycles. To enable practical clinical use outside shielded rooms, NV-center gradiometry was implemented, effectively suppressing common-mode noise thanks to the small sensor volume. The results across various magnetic environments lay the foundation for integrating quantum sensors into medical diagnostics, including MCG and magnetic encephalography.
A tiny defect in diamond is like a microscopic ear, able to pick up the magnetic 'breath' of the heart. Such sensors work at room temperature and are no bigger than a grain of sand.
To hear a faint signal in a noisy room, engineers used two sensors: just as our ears compare sound to discern speech, a pair of diamond 'ears' subtracts the magnetic background. This made it possible to record a magnetocardiogram without bulky shielding.
The irony is that the sensor is not a perfect diamond, but its flaw—a nitrogen atom next to a vacancy in the lattice. It is precisely this defect that, under the light of optical spectroscopy, turns into a supersensitive element. In the future, such sensors could form the basis of contactless diagnostic patches—cheaper and more portable than traditional magnetometers.
🎯 The heart's magnetic pulse was first captured in 1963—the setup was the size of a car and required expensive magnetic shielding.
🎬 The medical tricorder from Star Trek is closer than it seems: a compact diamond sensor reads magnetic rhythms without contact.