QTFM Gen-2

QTFM Gen-2 sensor head and control electronics

The QuSpin Total-Field Magnetometer (QTFM) is a compact, high-sensitivity hybrid scalar + three-axis vector atomic magnetometer for geophysical applications. It is extremely accurate, stable, and can resolve minute field changes. A compact, low-power package makes it ideal for use in a wide range of applications from magnetic observatories to small, mobile platforms such as UAVs.

Release Notes: link
(Archived Gen-1 webpage: link)

Technical Specifications (Preliminary)

Sensitivity: Scalar: <3 pT/√Hz; Vector: <0.1 nT/√Hz (optional add-on)
Data Rate: 1000 samples/sec (maximum)
Bandwidth: 500 Hz
Deadzone: Axial only, < +/- 7º cone about earth’s field (typical < 5º) (diagram)
Heading Error: <3 nT uncompensated
Dynamic Range: 1000 nT to 150,000 nT
Operating Temperature: -15 deg. C to 55 deg. C
Size: 17.7×19.8×35.8 mm (sensor head), 14.7×24.4×92.3 mm (ECU housing)
Weight: 12 grams for sensor head + 29 grams for electronics/ECU (ECU without housing is 6.5 g)
Power: +5 V input (using SCB) or 10-12 V input (sensor powered directly), 2.5 W total, 3.5 W during startup
Slew Rate Limit:  None
Outputs:  UART (RS232), USB 
Max Gradient Field: 300 nT/cm
Calibration: None
Type: Pulsed laser-pumped rubidium, free induction decay (link)


  • Optional add-on: Integrated, stable, low-noise three-axis vector outputs (synthetic1 )
  • Flat spectral response (no frequency-dependent response roll-off)
  • Built-in customizable digital filters (low-pass, high-pass, notch)
  • Multiple sensors can be precisely synchronized for gradiometry
  • Negligible dead zones
  • No slew rate limitations (can tolerate extremely magnetically noisy environments)
  • Built-in high-resolution frequency counter

1Vector outputs are synthetically derived (calculated) from scalar measurements by applying bias fields in interleaved measurement cycles (link)


Qty 1-3: $10,000
Qty 4-7: $8,500
Qty 8+: $8,000
Vector add-on: +$1,500
Please call for pricing for larger volumes or potential OEM applications.

User Guide
3D CAD files

  1. Standard Comms Board
  2. Triaxial Vector Upgrade
  3. Advanced Comms board
  4. Battery pack

Technical Support


Export Restrictions

QTFM is export controlled by the US Department of Commerce (ECCN: 6A006.a.2). QTFM can be shipped to most European countries, Japan, Australia, and South Korea without a license. Some key countries such as China, India, Russia are excluded and a license from the DOC is required before QTFM can be shipped to these countries.  A license approval can take over 8-12 weeks and requires detailed information on the end-user and end-use application.

A low-performance variant of the QTFM sensor (QTFM-B) with sensitivity worse than 20 pT/√Hz (ECCN: 6A996.a) is now available which can be shipped to nearly all countries without a license. The only operational difference between QTFM and QTFM-B is sensitivity.