Magnetic property characterization system employing a single sensing coil arrangement to measure AC susceptibility and DC moment of a sample
US5311125A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1992 |
| Grant date | May 10, 1994 |
| Priority date | — |
| Expiry date | Mar 18, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/72
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensing coil arrangement including a pair of sensing coils connected in opposition is used to measure AC susceptibility and, using sample movement and a DC magnetization field source, also to sense signals for absolute DC moment measurements. Since the same sensing coil arrangement is used for both AC and DC measurements, the measurements can be made successively in situ without removing the sample from a sample space (e.g., within a cryogenic chamber). This is a big advantage, because the changed conditions associated with removing and replacing a sample between measurements can cause confusing, uncorrelated results. A high speed voltmeter is used to perform the signal analysis for the moment measurement. The system can be configured to yield high resolution DC moment measurements to 25 ppm and sensitivities to better than 5.times.10.sup.-5 emu.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.