Patent US4847561A successfully refreshed from Google Patents.
US4847561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Domain and domain wall transition spectroscopy
Assignee: Individual
•
Filing: 1988-04-26
•
Granted: 1989-07-11
•
Expires: 2008-04-26
Abstract
Abstract This invention involves resonance enhancement of signals obtained from magnetic specimen undergoing changes in magnetic state. This is accomplished by placing the sample, magnetized by a quasi-static magnetic field, in a high frequency resonant cavity. By adjusting the resonance frequency of the sample-containing cavity so that it is resonant at a d.c. field corresponding to domain wall motion or domain rotation, clear signals can be obtained from the sample.
Inventors
- 👤 Ronald F. Soohoo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:52
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/60; G01R33/12; G01R33/123
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
231 words
A process for testing of a sample of magnetic material to determine the magnetic domain and domain wall spectra of said sample comprising the steps of: providing a magnetic sample having a certain magnetization, anisotropy, coercivity, and geometry; providing an adjustable resonant cavity into which high frequency radiation with a magnetic field along a first axis of said cavity is introduced; providing an adjustable high frequency source communicated to said adjustable resonant cavity; providing an adjustable quasi-static magnetic field communicated across said cavity, said adjustable quasi-static field being disposed at an angle to the magnetic field induced by said high frequency radiation in said adjustable cavity; computing the resonant frequency of said sample at a magnetic field H equal to the coercive force H c in said cavity as function of the magnetization of said sample, the anisotropy of said sample, the geometry of said sample; adjusting said adjustable resonant cavity to resonate at said computed resonant frequency of said sample; adjusting said adjustable high frequency source to said adjustable cavity resonance frequency, as well as to said resonance frequency of said sample in said cavity; plotting the power output from the cavity as a function of the quasi-static magnetic field H applied to the sample in the cavity to determine the magnetic transitions of the sample at a quasi-static magnetic field H nearly equal to the coercivity of the sample.
Claim 2
Dependent Claim
231 words
A process for testing of a sample of magnetic material to determine the magnetic domain and domain wall spectra of said sample comprising the steps of: providing a magnetic sample having a certain magnetization, anisotropy, coercivity, and geometry; providing an adjustable resonant cavity into which high frequency radiation with a magnetic field along a first axis of said cavity is introduced; providing an adjustable high frequency source communicated to said adjustable resonant cavity; providing an adjustable quasi-static magnetic field communicated across said cavity, said adjustable quasi-static field being disposed at an angle to the magnetic field induced by said high frequency radiation in said adjustable cavity; computing the resonant frequency of said sample at a magnetic field H equal to the coercive force H c in said cavity as function of the magnetization of said sample, the anisotropy of said sample, the geometry of said sample; adjusting said adjustable resonant cavity to resonate at said computed resonant frequency of said sample; adjusting said adjustable high frequency source to said adjustable cavity resonance frequency, as well as to said resonance frequency of said sample in said cavity; plotting the power output from the cavity as a function of the quasi-static magnetic field H applied to the sample in the cavity to determine the magnetic transitions of the sample at a quasi-static magnetic field H nearly equal to the coercivity of the sample.
References Cited (Backward Citations)
US3691453A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-10 | 1993-01-09 | 1993-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-10 | 1997-01-09 | 1997-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-10 | 2001-01-09 | 2001-07-11 | $7700.00 | Window Closed / Lapsed |