Abstract
Recent reports have demonstrated field resolutions of planar Hall effect magnetometers in the picotesla range. Here, we report a significant improvement in the field resolution of these sensors by decreasing their preamplifier white noise and the sensing element 1/f noise. We design, build, and test a miniature transformer-matched amplifier with a record noise level of 200 pV/ Hz and improve the fabrication process of the sensing element to increase its volume and reduce its associated 1/f noise. The magnetometer exhibits a magnetic resolution of ∼ 200 pT/ Hz at 1 Hz and ∼ 600 pT/ Hz at 0.1 Hz. These values are threefold better than previously reported results. The obtained resolution may enable applications for which high-end magnetometers, such as fluxgates, are currently used. We discuss routes for the further improvement of the magnetic field resolution.
| Original language | English |
|---|---|
| Article number | 7395273 |
| Pages (from-to) | 3224-3230 |
| Number of pages | 7 |
| Journal | IEEE Sensors Journal |
| Volume | 16 |
| Issue number | 9 |
| DOIs | |
| State | Published - 1 May 2016 |
Bibliographical note
Publisher Copyright:© 2016 IEEE.
Funding
This work was supported by Analog Devices, Inc.
| Funders | Funder number |
|---|---|
| Analog Devices |
Keywords
- Low noise amplifier
- Magnetic sensor
- Magnetometer
- Planar Hall effect
- Transformer noise matching