Honing quantum sensing
While quantum technologies have great long-term potential in computing applications, they are closer to practical use in sensing devices that will open new vistas in metrology, biology, neuroscience, and many other fields by enabling measurement of structures as small as individual photons, particles, and neurons. New research from MIT’s interdisciplinary Quantum Engineering Group (QEG) is addressing one of the fundamental challenges facing these quantum sensor systems: removing environmental noise from the signal being measured. The root of the problem, explains QEG doctoral student David Layden, is the extreme sensitivity of quantum sensors to their surrounding environment. These sensors typically start in a quantum superposition of two distinct states. Minuscule external forces induce a phase variation between the two states that can be leveraged to measure physical quantities like temperature, motion, and electric and magnetic fields with unprecedented resolution. But this same sensitivity means that the sensors are also picking up many extraneous environmental...