Superconducting magnetic field sensing apparatus having digital output, on-chip quantum flux packet feedback and high bias margins
Patent 5248941 Issued on September 28, 1993. Estimated Expiration Date: 
April 17, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
April 17, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesFluxoid type superconducting logic element Superconducting switching circuit, memory cell and memory circuit, with resonance damping resistors Superconducting current detecting circuit employing DC flux parametron circuit Superconducting circuit Digital SQUID control system for measuring a weak magnetic flux Patent #: 5045788 InventorsApplicationNo. 686714 filed on 04/17/1991US Classes:324/248, Superconductive magnetometers327/527, Superconductive (e.g., cryogenic, etc.) device505/846Using superconductive quantum interference device (i.e., SQUID): (Class 324/248)ExaminersPrimary: Strecker, Gerard R.Assistant: Edmonds, Warren S. International ClassG01R 033/035AbstractA magnetometer having high sensitivity and high resolution is achieved using superconductive circuit elements. The magnetometer includes a pick-up coil, amplifying transformer quantum flux parametron (QFP), latch, feedback gate and feedback inductor fabricated with superconducting elements and coupled to a bidirectional counter. The magnetometer implements an on-chip negative feedback loop. The pick-up coil senses an external magnetic field or gradient resulting in an induced current which is amplified and fed to the QFP which generates a directional indicator signal sent to the latch. When the polarity of the indicator is indicated as corresponding to the polarity of a latch clock signal, a current signal is sent to the feedback gate causing a packet of quantum flux to be generated. The packet is fed back through the feedback inductor, inducing a current in the pick-up coil which opposes the induced current attributable to the external magnetic field. When the induced current in the pick-up coil attributable to the external magnetic field is offset by the induced current attributable to the feedback flux, the magnetometer stabilizes.Other References
Field of SearchMagnetometersSuperconductive magnetometers Measuring and testing: (Classes 73, 324, 356, and 374) Electrical: (Class 324) Nuclear magnetic resonance (NMR) system or device: (Class 324) Magnetometer: (Class 324/248) Using superconductive quantum interference device (i.e., SQUID): (Class 324/248) | |
