Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Distributive type parameters
Reexamination Certificate
2007-09-11
2007-09-11
Benson, Walter (Department: 2858)
Electricity: measuring and testing
Impedance, admittance or other quantities representative of...
Distributive type parameters
C324S724000, C324S248000, C324S244000
Reexamination Certificate
active
11162057
ABSTRACT:
An apparatus for measuring spin polarization via Point Contact Andreev Reflection (PCAR) at a magnet-superconductor junction, with variable magnetic fields and temperature control. A cryostat probe investigates superconducting energy gap and Andreev reflection in superconductor-half metal junctions, in a wide range of magnetic fields and temperature from 2K-300K. The cryostat probe is integrated with a commercial physical properties measurement system. The measurement probe includes a rotary-translation stage with coarse and fine screws that enable a user to make point contacts in a cryogenic, evacuated environment where the point contact junction can be controlled at room temperature by turning a knob. Copper wires are connected as electrical leads from an aluminum housing, descend down to a copper housing, for measurement, when contact is made by tip with a half-metal sample, such as CrO2. External current and voltage meters measure the current-voltage characteristics and data acquisition is performed using computer interface.
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Hariharan Srikanth
Sanders Jeff T.
Benson Walter
Smith Ronald E.
Smith & Hopen , P.A.
University of South Florida
Valone Thomas
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