Generalized Ginzburg-Landau theory for the magnetostatics of ferromagnetic superconductors

Journal Article · Wed Oct 01 04:00:00 EDT 1980 · Phys. Rev., B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.22.3183· OSTI ID:5092604

Grewe, N; Schuh, B

The phase diagram of ferromagnetic superconductors is investigated on the basis of a semimacroscopic free-energy functional. A self-consistent decoupling of the fourth-order term in the magnetization sigma-arrow-right and the assumption of a homogeneous modulus psi/sub 0/ of the superconducting order parameter psi allows one to integrate out the fluctuating parts of magnetization and magnetic induction B as well as the phase of psi. The resulting free-energy function depends only on the homogeneous parts psi/sub 0/, sigma-arrow-right/sub 0/, and B/sub 0/. The thermodynamically stable states can be found by minimization. We present model calculations for the phase diagram and discuss the order of the transitions involved. Good agreement with recent measurements including specific-heat data is obtained. The possible occurrence of a coexisting phase is discussed in the frame of our model.

• Research Organization: Institut fuer Theoretische Physik der Universitaet zu Koln, 5000 Koln 41, Zulpicher Strasse 77, West Germany
• OSTI ID: 5092604
• Journal Information: Phys. Rev., B: Condens. Matter; (United States), Journal Name: Phys. Rev., B: Condens. Matter; (United States) Vol. 22:7; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

656102* -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DIAGRAMS
ENERGY
FERROMAGNETIC MATERIALS
FREE ENERGY
GINZBURG-LANDAU THEORY
MAGNETIC MATERIALS
MAGNETIZATION
MATERIALS
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SPECIFIC HEAT
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES