Local structure and magnetic properties of B2- and B20-like ultrathin Mn films grown on Si(001)
- Dalhousie U.
The structural and magnetic properties of ultrathin Mn layers deposited onto Si(001) by molecular beam epitaxy at low temperature are reported. X-ray absorption fine structure studies reveal that the structure of the silicide layer that forms depends on the growth temperature of the capping layer. A capping layer grown at 200 C on 0.35-monolayer (ML) Mn results in a metastable MnSi phase with a B2-like (CsCl) structure, whereas a cap grown at room temperature on 0.5 ML followed by annealing at 200 C produces a lower coordinated MnSi phase with a B20-like structure. Increasing the Mn thickness from 0.5 to 4 monolayers does not trigger a structural transformation but drives the structure closer to MnSi-B20. The sample with B2-like structure has the largest Mn magnetic moment of 0.33 {mu}{sub B}/Mn at T = 2 K, and a Curie temperature T{sub c} above 250 K. MnSi-B20 layers showed lower moments and much lower T{sub c}'s, in line with those reported for MnSi-B20 thin films.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
- Sponsoring Organization:
- FOREIGN
- OSTI ID:
- 1034192
- Journal Information:
- Phys. Rev. B, Vol. 85, Issue (1) ; 01, 2012
- Country of Publication:
- United States
- Language:
- ENGLISH
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