Sensor and method for indicating the presence of a low magnetic field using high critical temperature superconductor ceramic material to absorb electromagnetic energy
This patent describes a sensor for use with a source of electromagnetic energy for indicating the presence of a low magnetic field with a sensitivity of at least 10{sup {minus} 10} tesla. It comprises: a sensing element consisting essentially of a high critical temperature superconductor ceramic oxide material without the need for further processing, said critical temperature being above 77{degrees}; means for cooling the sensing element to a temperature below the critical temperature of the superconductor material whereby the sensing element becomes superconducting; means for applying electromagnetic energy from the source to the sensing element whereby a first portion of the applied energy is absorbed by the sensing element; means for detecting the amount of the energy absorbed by the sensing element; and means modulating the sensing element for providing a reference signal for phase-sensitive detection and for biasing the electromagnetic energy absorption characteristics of the sensing element to a predetermined absorption reference value.
- Assignee:
- Drexel University, Philadelphia, PA
- Patent Number(s):
- A; US 4906607
- Application Number:
- PPN: US 7-178160A
- OSTI ID:
- 6973954
- Country of Publication:
- United States
- Language:
- English
Similar Records
Off-line-locked laser diode species monitor system
Combustible gas sensor
Related Subjects
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
42 ENGINEERING
420500 -- Engineering-- Materials Testing
440800 -- Miscellaneous Instrumentation-- (1990-)
47 OTHER INSTRUMENTATION
CERAMICS
DESIGN
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
MAGNETIC FIELDS
MAGNETIC TESTING
MATERIALS TESTING
MEASURING INSTRUMENTS
NONDESTRUCTIVE TESTING
PHYSICAL PROPERTIES
SUPERCONDUCTIVITY
TESTING
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE