A quantum diamond microscope contains a doped diamond slide that is excited by tiny magnetic fields. By Paul VoosenOn a table inside the magnetically shielded lab of Roger Fu, a planetary scientist at Harvard University, sits a modest contraption that is telling profound stories about the geologic past.
The quantum diamond microscope (QDM) consists of a few electromagnetic coils wrapped around a camera, a small laser, and what looks like a rose-tinted sample slide.
The slide is not glass, however; it is a diamond, doped with defects sensitive to tiny magnetic fields. Using this diamond sensor, the microscope can map the fields imprinted in rock grains at scales smaller than the width of a human hair, allowing geologists to tease out history