Modified two-fluid model of conductivity for superconducting surface resistance calculation. Master's thesis

Technical Report · Sat May 01 04:00:00 EDT 1993

OSTI ID:5830095

Linden, D S

The traditional two-fluid model of superconducting conductivity was modified to make it accurate, while remaining fast, for designing and simulating microwave devices. The modification reflects the BCS coherence effects in the conductivity of a superconductor, and is incorporated through the ratio of normal to superconducting electrons. This modified ratio is a simple analytical expression which depends on frequency, temperature and material parameters. This modified two-fluid model allows accurate and rapid calculation of the microwave surface impedance of a superconductor in the clean and dirty limits and in the weak- and strong-coupled regimes. The model compares well with surface resistance data for Nb and provides insight into Nb3Sn and Y1Ba2Cu3O(7-delta). Numerical calculations with the modified two-fluid model are an order of magnitude faster than the quasi-classical program by Zimmermann (1), and two to five orders of magnitude faster than Halbritter's BCS program (2) for surface resistance.

• Research Organization: Air Force Inst. of Tech., Wright-Patterson AFB, OH (United States)
• OSTI ID: 5830095
• Report Number(s): AD-A-267549/4/XAB; AFIT/CI/CIA--93-077
• Country of Publication: United States
• Language: English

Related Subjects

665410* -- Superconductivity-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
ANALYTICAL SOLUTION
BARIUM COMPOUNDS
BARIUM OXIDES
BCS THEORY
CHALCOGENIDES
COMPUTER CALCULATIONS
COPPER COMPOUNDS
CUPRATES
DESIGN
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRONIC EQUIPMENT
EQUIPMENT
FLUID MECHANICS
FREQUENCY DEPENDENCE
HIGH-TC SUPERCONDUCTORS
MATHEMATICAL MODELS
MECHANICS
MICROWAVE EQUIPMENT
NIOBIUM COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
REFRACTORY METAL COMPOUNDS
SUPERCONDUCTORS
TEMPERATURE DEPENDENCE
TIN COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES