Quantum Sensing

Quantum sensing uses the same quantum mechanics as computing, superposition and interference, to measure physical quantities, time, magnetic fields, gravity, rotation, electric fields, more precisely than classical sensors. The key difference from quantum computing is that a sensor works with one or a few quantum systems and reads how the environment shifts their state, so the noise a computer fights is the signal a sensor wants, and no error correction or large qubit array is needed. The main workhorses are nitrogen-vacancy centers in diamond, which measure magnetic fields at nanometer scale at room temperature, atomic clocks and atom interferometers, which measure time and gravity, Rydberg atoms, which detect radio and microwave fields, and superconducting SQUID loops for the most sensitive magnetometry. Because the hardware already exists and the use cases are concrete, navigation without GPS, mineral and oil surveying, medical imaging, quantum sensing is the quantum technology that generates commercial revenue today while quantum computing still works through its roadmap.