Phase transition of an itinerant-electron antiferromagnet

Journal Article · Sat Dec 01 04:00:00 EST 1973 · J. Low Temp. Phys., v. 13, no. 5/6, pp. 525-551

DOI:https://doi.org/10.1007/BF00656544· OSTI ID:4375748

Fenton, E W

ABS>A weak-coupling theory of the itinerant-electron antiferromagnet for T > T/sub c/ is described. Vertex and self-energy parts are treated self- consistently using Ward -- Pitaevskii identities. The weak-coupling criterion is that the scalar three-vertex must be suitably small. This condition is not satisfied right down to T/sub c/; however, it is satisfied in a region near T/sub c/ where the corrections to the bare electron-- electron interaction are not small. Expressions are derived for the specific heat, temperature derivative of the electrical resistivity, etc., which are all proportional to the weakly singular form STAT/sub c//(T-T/sub c/)!/sub n/, with h << 1. An analogous theory applies for superconductors. In this case the weak-coupling exponent h is approximately equal to (T/sub //E/sub F/)/sub 2/. This quantity is typically 10/ sup-8/-10/sup -7/ for superconductors, and in the weak-coupling temperature regime the lambda curve singularity would not be observable experimentally. However, for an itinerant-electron antiferromagnet such as chromium, the quasicubic shape of the electron and hole Fermi surfaces causes enhancement of h to a value of order 10/sup -1/. For chromium the theory is consistent with experimental results and with a recent theory by Dzyaloshinskii and Kats (using a different method). (auth)

• Research Organization: National Research Council of Canada, Ottawa
• Sponsoring Organization: USDOE
• NSA Number: NSA-29-014062
• OSTI ID: 4375748
• Journal Information: J. Low Temp. Phys., v. 13, no. 5/6, pp. 525-551, Journal Name: J. Low Temp. Phys., v. 13, no. 5/6, pp. 525-551; ISSN JLTPA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*ANTIFERROMAGNETIC MATERIALS-- PHASE TRANSFORMATIONS
*SUPERCONDUCTORS-- PHASE TRANSFORMATIONS
CHROMIUM
ELECTRIC CONDUCTIVITY
FERMI LEVEL
N66200* --Physics (Low Temperature)--Superconductivity
SPECIFIC HEAT