Role of film roughness and interdiffusion in the formation of nonferromagnetic fcc Fe in the Fe/Co(100) system

Journal Article · Tue Apr 01 04:00:00 EST 1997 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.365537· OSTI ID:565299

Escorcia-Aparicio, E J; Kawakami, R K; Choi, H J ^[1]; Qiu, Z Q ^[2]

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1. Department of Physics, University of California at Berkeley, Berkeley, California 94720 (United States)
2. Department of Physics, University of California at Berkeley, Berkeley, California (United States)

The fcc Fe/Cu(100) and Fe/Co(100) systems are characterized by a wide range of magnetic and structural phases. In particular, a nonferromagnetic fcc phase with a live layer has been observed for room temperature growth Fe films in the {approximately}5{endash}11 ML thickness range. This nonferromagnetic phase is not present for low temperature ({approximately}120 K) grown films even when the film temperature is raised to room temperature. Annealing the film at 475 K, however, will recover the room temperature phase. Two effects that could account for these features are interdiffusion and surface smoothening. In order to determine which of these effects is responsible for the occurrence of the nonferromagnetic phase, we performed experiments on the Fe/Co(100) system to separate these two effects. An artificially roughened sample grown at room temperature exhibits a ferromagnetic phase only. A sample grown at low temperature in which the first few layers are alloyed to simulate interdiffusion also shows the ferromagnetic phase. Experiments in which a few layers of varying thicknesses are grown at room temperature and the rest of the film is grown at low temperature exhibit different magnetic phases depending on the thickness of the room temperature grown layer. These results indicate that film roughness is the main factor that determines whether the nonferromagnetic phase of fcc Fe will be present in the {approximately}5{endash}11 ML thickness range. {copyright}{ital 1997 American Institute of Physics.}

• Research Organization: Lawrence Berkeley National Laboratory
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 565299
• Report Number(s): CONF-961141--
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 81; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
COBALT
DIFFUSION
FERROMAGNETIC MATERIALS
IRON
LAWRENCE BERKELEY LABORATORY
MAGNETIC PROPERTIES
PHASE TRANSFORMATIONS
ROUGHNESS
THIN FILMS