MIT researchers have developed a new, ultrasensitive magnetic-field detector that is 1,000 times more energy-efficient than its predecessors. It could lead to miniaturized, battery-powered devices for medical and materials imaging, contraband detection, and even geological exploration. 

Magnetic-field detectors (magnetometers) are already used for all those applications. But existing technologies have drawbacks: Some rely on gas-filled chambers; others work only in narrow frequency bands, limiting their utility.

A pure diamond is a lattice of carbon atoms, which don’t interact with magnetic fields. A nitrogen vacancy is a missing atom in the lattice, adjacent to a nitrogen atom. Electrons in the vacancy do interact with magnetic fields, which is why they’re useful for sensing.

Synthetic diamonds with nitrogen vacancies (NVs) — defects that are extremely sensitive to magnetic fields — would offer a solution. A diamond chip about one-twentieth the size of a thumbnail could contain trillions of nitrogen vacancies, each capable of performing its own magnetic-field measurement.

The problem has been aggregating all those measurements.

Probing a nitrogen vacancy requires zapping it with laser light, which it absorbs and re-emits. The intensity of the emitted light carries information about the vacancy’s magnetic state.

“In the past, only a small fraction of the pump light was used to excite a small fraction of the NVs,” says Dirk Englund, the Jamieson Career Development Assistant Professor in Electrical Engineering and Computer Science and one of the designers of the new device. “We make use of almost all the pump light to measure almost all of the NVs.”

With the improvement of CVD synthesis technology, through the adoption of gas raw material (hydrogen, methane), Luoyang Yuxin Diamond Co., Ltd get the completely transparent and colorless large size diamond single crystal under less than one air pressure, the temperature of 800-1200 ℃ by epitaxial growth way, its composition, hardness, density, etc. are basically identical with natural diamond, but the price is much lower than that of natural diamond; different from the method of high temperature and high pressure (HTHP), CVD artificial synthetic technique does not need to use the catalyst, and puts an end to forming metal inclusions, cracks, holes, etc. in the production.

Features: after polishing, the clarity is commonly VVS and above level, color chromaticity of D-J.

We can provide raw diamond at carat level.