Paragraf has employed its expertise in manufacturing and implementing graphene technology to make a major advance in Hall sensor performance. The company offers a new sensor range capable of unmatched sensitivity and linearity when installed in low-temperature environments and strong magnetic fields.
Tested at the HFML at Radboud University Nijmegen, the GHS-C sensors aid operation in magnetic fields up to 30T and at cryogenic temperatures (down to 1.5K). The sensors produce a degree of accuracy that has not previously been feasible under these conditions, sustaining non-linearity errors of significantly less than 1% across the entire measurement range.
The transformative magnetic field measurement abilities of the devices are due to the graphene sensor elements. Graphene’s inherent high electron mobility directly transposes into high sensitivity capability, supported across the complete magnetic field range – making these devices far simpler to calibrate.
Examples of suitable applications include low-temperature quantum computing, high-field magnet monitoring in next-generation MRI systems, particle accelerators, fusion energy field control, and other scientific and medical instrumentation. The sensors can also be directly employed in fundamental physics experiments, e.g., quantum physics research, superconductivity and spintronics.
“Under cryogenic temperatures and in extremely high magnetic fields, the sensitivity performance of other high-end Hall sensors drops off acutely. This is due to interactions occurring between the different layers of the sensor element. It leads to linearity issues that curb their range, as well as making them incredibly difficult to calibrate. Consequently, the best achievable accuracy of these sensors becomes significantly limited above around 16 T,” states Paragraf’s CEO, Simon Thomas.
He continued: “By relying on 2D graphene sensor elements, we can circumvent this problem completely. It means there are no interactions to impinge on performance and linearity, as well as enabling symmetrical outputs, with no hysteresis, to be derived. We are grateful to the team at HFML for their assistance in helping us prove the ultra-high magnetic field capabilities of our sensors.”
Paragraf and HFML will hold a joint webinar on 1 December 2021 to share and discuss the results of the tests.