6533b7dbfe1ef96bd126ff35
RESEARCH PRODUCT
Surface order in body-centered cubic alloys
Friederike Schmidsubject
Surface (mathematics)Materials scienceSingularityMean field theoryCondensed matter physicsField (physics)Monte Carlo methodBinary numberGeneral Materials ScienceCubic crystal systemCondensed Matter PhysicsCritical exponentElectronic Optical and Magnetic Materialsdescription
Free (100)-surfaces of body-centered cubic binary alloys are studied in a parameter range where the bulk turns from the ordered B2-phase to the disordered A2-phase. A model is chosen that describes iron-aluminium alloys in a fairly realistic way. Mean field treatments and Monte Carlo investigations both show that under certain circumstances the surface remains ordered far above the bulk disordering temperatureT c, though the surface order parameter and the surface susceptibility exhibit a singularity atT c with critical exponents characteristic for the ordinary transition. One finds, that if the surface is nonstoechiometric and different layers are not equivalent with respect to perfect bulk ordering, this induces an effective ordering field at the surface. Finally surface potentials are introduced into the model. Realistic values are determined by mean field considerations from experimental data and their effect on the surface is discussed.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1993-03-01 | Zeitschrift f�r Physik B Condensed Matter |