Diamond Compass Sees Atoms ⚡ экспресс
Spins in solids, such as nitrogen-vacancy centers in diamond, are promising elements for quantum computing and sensing, where nanoscale control of individual spins is required. To determine the resolution limit of this approach, Fourier magnetic imaging of NV centers was performed under optimized conditions. A compact experimental platform with thermal drift compensation at room temperature was built, generating a pulsed magnetic field gradient of up to 13.5 Gs/µm. Using the Fourier magnetic imaging protocol, a single NV center was localized with a spatial resolution of 0.28 ± 0.10 nm and a field measurement deviation of just 9 nT. The technique opens up possibilities for localizing spins inside proteins and cells.
In the crystal lattice of diamond, defects occasionally appear: a nitrogen atom grabs a foreign spot, and next to it gapes a void. Such a flaw turns into a supersensitive diamond compass—its magnetic needle quivers at the slightest external field. Paradoxically, a blemish that lowers a stone's value has become a coveted tool for physicists.
To see this atom-sized compass, scientists built a tiny platform unfazed by temperature fluctuations. They 'hailed' the defect with a series of magnetic pulses and caught the echo—a faint response. Magnetic scanning decoded the signal and pinpointed the spot with staggering precision of 0.28 nanometers—smaller than the distance between atoms in a crystal.
Underpinning this is the quantum nature of the defect: its magnetic moment can act as a qubit—the information unit of a quantum computer. Now we can probe such 'compasses' inside proteins and living cells, bringing us closer to the era of molecular medicine.
🎯 These defects are so sensitive they detect the magnetic field of a single proton—it's like hearing a whisper from across an ocean.