Electricity: measuring and testing – Magnetic – Magnetometers
Reexamination Certificate
2007-01-23
2007-01-23
Lefkowitz, Edward (Department: 2862)
Electricity: measuring and testing
Magnetic
Magnetometers
Reexamination Certificate
active
10679905
ABSTRACT:
A method and apparatus for determining volume and anisotropy field distribution of thin film granular material includes the use of a magneto-optic probe, a lock-in amplifier, and a computer. The magneto-optic probe utilizes the Kerr effect in order to determine the transverse AC susceptibility of the sample. The Lock-in amplifier determines the complex parameters of the susceptibility as a function of the DC field and AC frequency. Separate distribution values of anisotropy field and grain volume can then be determined mathematically from the relationship of complex susceptibility parameters to the DC field strength.
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Chantrell Roy W.
Ju Ganping
Weller Dieter K.
Zhou Hong
Kinney & Lange PA
Lefkowitz Edward
Schindler David M.
Seagate Technology LLC
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