Paragraf is a Cambridge-based startup that was spun out of Cambridge University's Department of Materials Engineering. Paragraf has created a patented graphene deposition technique on silicon, SiO2, sapphire, and other semiconducting substrates.
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This method is flexible and compatible with current production procedures for electrical devices. Their initial product, a graphene Hall-effect sensor for detecting magnetic fields in harsh conditions, was developed and commercialized. Galanis and Allan are the product owners of the graphene Hall sensor and the graphene fabrication and device manufacturing lead at Paragraf, respectively.
For the last decade, graphene has been the most thoroughly investigated 2D material and with good reason.
As graphene is just one atom thick, its use could lead to a day when electronics will be flexible, transparent, and resistant to the impacts of stray magnetic fields, all of which are critical for developing elevated Hall effect sensors.
Benefits of Graphene Sensors
Excellent quality graphene with extremely high mobility may be incorporated into sensing technologies thanks to Paragraf's contamination-free direct-to-wafer deposition method. Resistance to in-plane stray fields resulting in substantially lower insulating requirements, high sensitivity and low distortion, reliability with no oscillation and no saturation in yield, and implementation at mK with relatively low heat input are all advantages of graphene Hall effect sensors.
GHS-C, A Graphene-Based Hall Sensor for Quantum Computing
The GHS-C, a graphene-based Hall sensor designed for high field observations while functioning at extremely low temperatures, has reached volume production at Paragraf. It does this with almost negligible heat dissipation.
The cryogenic sensor also enables cold bore measurements without room temperature inserts, resulting in high-quality data and significant time savings. One of the major obstacles that scientists and developers working at very low temperatures encounter when striving for high sensitivity is the instability created by the heat wasted by traditional sensors.
When working with low - temperature applications, such as quantum computing, this is very important. Instead of mWs, GHS-C dissipates nW of heat. This has a far lower influence on the instrument, enabling researchers to take more precise and reproducible measurements.
More precise analysis of material characteristics at temperature extremes and magnetic forces is one of the advantages of the GHS-C sensor.
The GHS-C also has a very low power consumption, which keeps the heat load on the frigid fingers to a minimum. The GHS-C seems to be the only Hall sensor in mass production today that can achieve this performance level at temperatures lower than 3 K.
The technology involved can operate at much lower temperatures without losing performance. This is made feasible by graphene's absence of a planar Hall Effect, a distinctive property that Paragraf has exploited.
The GHS-C sensor allows commercial organizations to precisely detect high strong magnetic strengths at extremely low temperatures, allowing them to increase production throughput by replacing traditional NMR probe mapping procedures with faster magnet imaging. The cryogenic sensors also permit measurements in cold bore, eliminating the requirement for ambient temperature inserts and enabling faster data collecting.
Applications of GHS-C, Paragraf's New Graphene Sensor
The GHS-C employs graphene that has been optimized and tailored for high-field applications such as superconduction, quantum computing, high-energy thermodynamics, low-temperature physics, fusion, and space exploration.
Furthermore, since the next era of particle accelerators will depend on magnets with field strengths greater than 16 T, the GHS-C is already attracting attention from industry experts.
The already sizable worldwide magnetic sensor industry (of which Hall-Effect sensors account for the bulk) is continuously rising. Despite their extensive use, there is still room to expand the use of Hall-Effect sensor applications, especially with higher-performance devices, and there is a clear chance for graphene to demonstrate its worth.
As we have seen, typical Hall-Effect sensor devices have several limitations in terms of sensitivity, precision, and the impact of temperature on their performance. Paragraf's new graphene-based GHS series sensors will be capable of supporting operating parameters that are well above what can be achieved by traditional devices.
Because graphene is a two-dimensional material (with a subatomic particle thickness), it does not suffer from the typical planar Hall-Effect problems, with the sensor element simply registering the perpendicular magnetic field.
Continue reading: Ultra-Sensitive Graphene-Based Sensors for Next-Generation Surgical Robotics
References and Further Reading
Paragraf (2020) Paragraf partners with CERN to demonstrate unique properties of Paragraf's new Graphene Hall Effect Sensor. [online]. Available at: https://www.paragraf.com/news/paragraf-partners-with-cern-to-demonstrate-unique-properties-of-paragrafs-new-graphene-hall-effect-sensor/
Tibbetts, J., (2019) Quantum computing and cryptography: Analysis, risks, and recommendations for decisionmakers. United States. [online] Available at: https://doi.org/10.2172/1566798