To guarantee high quality pharmaceuticals, manufacturers need not only to control the purity and concentration of their own products, but also those of their suppliers. Researchers at the Fraunhofer Institute for Applied Solid State Physics IAF have developed a measuring system capable of i ... more
Sensor the size of a nitrogen atom investigates hard drives
Integrated circuitry is becoming increasingly complex. These days a Pentium processor contains some 30 million transistors. And the magnetic structures found in hard drives measure just 10 to 20 nanometers across – less than a flu virus at 80 to 120 nanometers in diameter. Dimensions are rapidly approaching the realm of quantum physics and, already, researchers at the Fraunhofer Institute for Applied Solid State Physics IAF in Freiburg are applying themselves to the quantum technology challenges of tomorrow. Together with colleagues at the Max Planck Institute for Solid State Research, they are developing a quantum sensor that will be able to precisely measure the tiny magnetic fields we can expect to see in the next generation of hard discs. The sensor itself is just slightly larger than a nitrogen atom, with a synthetic diamond to act as a substrate.
Diamond has a variety of advantages quite apart from its considerable mechanical and chemical stability. For instance, one can implant foreign atoms such as boron or phosphorus, thereby turning the crystals into semiconductors. Diamond is also the perfect material for optical circuits. But perhaps its greatest attribute is its impressive thermal conductivity, with the strength of the carbon atom bonds ensuring that heat is rapidly dissipated.
Over the past decades, Fraunhofer IAF has developed optimized systems for producing diamonds. The process for mass production takes places in a plasma reactor, and Freiburg possesses many of these silver-colored devices. Plasma is ignited to generate temperatures of 800 to 900 degrees Celsius so that, when gas is fed into the chamber, diamond layers can form on the square-shaped substrate. The diamond crystals have an edge length of between three and eight millimeters, and are then separated from the substrate and polished using a laser.
Preparing the diamond to act as a magnetic detector
Manufacturing the innovative quantum sensor requires a particularly pure crystal, which has inspired further improvements in the process. For instance, in order to grow ultra-pure diamond layers, the methane that provides the carbon for the diamond is pre-filtered using a zirconium filter. On top of that, the gas must be isotopically pure, since only 12C – a stable isotope of the carbon atom – has zero nuclear spin, which is a prerequisite for the magnetic sensor later on. The hydrogen also undergoes a purification process, after which the ultra-pure single crystal diamond must be prepared for its role as a magnetic detector. Here there are two options: either you insert a single nitrogen atom into the extremely fine tip, or you add nitrogen at the final phase of the diamond production process. After that, the diamond tip is honed in oxygen plasma using an etching process in the institute’s own cleanroom. The final result is an extremely fine diamond tip that resembles that of an atomic force microscope. The key to the whole design is the added nitrogen atom together with a neighboring vacancy in the crystal structure.
This combined nitrogen-vacancy center acts as the actual sensor, emitting light when it is exposed to a laser and microwaves. If there is a magnet nearby, it will vary in its light emission. Experts call this electron spin resonance spectroscopy. Not only can this technique detect magnetic fields with nanometer accuracy, it can determine their force as well, opening up an extraordinary range of applications. For instance, the tiny diamond tips can be used to monitor hard drive quality. These data storage devices are tightly packed and there are always tiny errors. The quantum sensor can identify defective data segments so that they are excluded from the disc reading and writing process. This reduces the defect rate, which is soaring as miniaturization continues apace, and cuts down on production costs.
Quantum sensors could measure brain activity
The tiny sensor can potentially be applied in a wide range of scenarios, since there are weak magnetic fields everywhere, even in the brain. “Whenever electrons move, they generate a magnetic field,” says IAF expert Christoph Nebel. So when we think or feel, our brains are generating magnetic fields. Researchers are keen to localize this brain activity to determine the areas of the brain that are responsible for a certain function or feeling. This can be done directly by measuring brainwaves using electrodes, but the results are very imprecise. Magnetic field measurements offer far better results. However, the sensors in use at the moment have one significant disadvantage in that they must be cooled with liquid nitrogen. Drawing on the extreme thermal conductivity of diamond, the new technology can operate at room temperature without the need for any cooling. For this application, instead of using fine tips you would use tiny platelets that incorporate multiple nitrogen-vacancy centers. Each center supplies a point in the image and, together, a detailed picture.
Currently, however, Christoph Nebel and his team are focusing their attention on researching and optimizing diamond as a high-tech material. This application in quantum sensor technology is a promising beginning.
- quantum technology
- quantum sensors
- magnetic fields
- magnetic field detection
Together with partners from research and industry, Fraunhofer IAF has developed a hand-held scanner for hazardous substances within the EU project CHEQUERS. The sensor detects explosive, toxic and other dangerous substances in real time and will help emergency personnel with on-site detecti ... more
Imagine holding two different medications in your hands, one being the original, the other one being a counterfeit. Both appear exactly the same. Is there any way for you to distinguish them? The answer is: yes. Our quantum cascade laser (QCL) has the ability to identify substances in a spl ... more
Without the Higgs mechanism, particles would have no mass. The Higgs boson, which was discovered in 2012, is therefore also referred to as the “God particle”. It arises as an oscillating excitation of the Higgs field, which penetrates the world. Superconductivity displays similar properties ... more
Processes taking place inside tiny electronic components or in molecules can now be filmed at a resolution of a few hundred attoseconds and down to the individual atom. The operation of components for future computers can now be filmed in HD quality, so to speak. Manish Garg and Klaus Kern, ... more
For the first time, researchers at Empa and the Max Planck Institute for Solid State Research have succeeded in "growing" single-wall carbon nanotubes (CNT) with a single predefined structure - and hence with identical electronic properties. And here is how they pulled it off: the CNTs "ass ... more
Microscopy is at the forefront of the fight against the coronavirus. Special microscopes, which enable scientists to view minute cell structures, are an indispensable tool in the development of vaccines and new therapies. Such equipment comprises not only a microscope with high optical reso ... more
The air we exhale contains information that can assist with the diagnosis of disease. Researchers at the Fraunhofer Project Hub for Microelectronic and Optical Systems for Biomedicine MEOS are now developing solutions designed to enable the analysis of breath gas for this purpose. Although ... more
The need for everyday objects with antiviral surfaces is high due to the COVID 19 pandemic. It is known that the material composition of an object has an influence on the viability of viruses on surfaces. This is where the work of the Fraunhofer IFAM comes in: In cross-disciplinary research ... more
We communicate at eye level for customer oriented development ✓ We cover the process from idea generation over feasibility studies to prototyping ✓ Tailor-made detection systems for a wide range of analytes - biomarkers, germs, toxins and more ✓ more
One-stop-shop for the development of system control boards for IVD applications using modular electronics ✓ System integration & interoperability testing: Libraries for medical data communication-POCT1-A, POCT1-A2 ✓ Digital Pathology and Medical Image Processing for Microscopy and Endoscopy ... more
Digitalization and artificial intelligence are changing diagnostics in clinical routine and pharmaceutical research. New IVD devices are coming out, laboratory data is connected to the hospital IT system and AI-based image analysis enables new and efficient processes in digital pathology an ... more
At Fraunhofer IZI-BB we develop analytical and biotechnological solutions for medical issues, animal health, food, cosmetics and the environment. Our research focuses on sample preparation, development of molecular recognition elements and data acquisition as well as miniaturization and aut ... more
- 1Detect neurodegenerative diseases such as Alzheimer's by a simple eye scan?
- 2Fluorescence microscopy at highest spatial and temporal resolution
- 3The Mechanics of the Immune System
- 4Resolve Biosciences Launches New Era in Single-Cell Spatial Analysis
- 5Quick look under the skin
- 6New ion trap to create the world's most accurate mass spectrometer
- 7How does your computer smell?
- 8Clocking electron movements inside an atom
- 9Sartorius closes 2020 with strong growth
- 10A clear path to better insights into biomolecules