Abstract
The extension of small, inexpensive, low-power, low-frequency, ultra-sensitive magnetic sensors to fields between 1 nT and 1 pT, an area currently dominated by fluxgates, optically pumped magnetometers, and SQUIDS, would be a paradigm shift for the field of magnetic sensors. The necessary elements for picoTesla magnetic-tunnel-junction (MTJ) sensors have been identified by modeling the noise characteristics. The results help identify the experimental challenges involved in the integration of these necessary elements into actual sensors, illustrate the trade-offs faced if there are losses in performance upon integration. Scanning electron microscopy with polarization analysis (SEMPA) of the pinned layer provides insights into problems and possible solutions. Issues associated with real-world applications of these sensors to ultra-low field measurements are discussed.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 217-225 |
| Number of pages | 9 |
| Journal | Sensors and Actuators, A: Physical |
| Volume | 155 |
| Issue number | 2 |
| DOIs | |
| State | Published - Oct 2009 |
| Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Instrumentation
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
Keywords
- Magnetic sensors
- Magnetic-tunnel-junction
- Tunneling magnetoresistance
- picoTesla