Strain-induced high ferromagnetic transition temperature of MnAs epilayer grown on GaAs (110)
1 State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, China
2 National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
Nanoscale Research Letters 2011, 6:125 doi:10.1186/1556-276X-6-125Published: 9 February 2011
MnAs films are grown on GaAs surfaces by molecular beam epitaxy. Specular and grazing incidence X-ray diffractions are used to study the influence of different strain states of MnAs/GaAs (110) and MnAs/GaAs (001) on the first-order magnetostructural phase transition. It comes out that the first-order magnetostructural phase transition temperature Tt, at which the remnant magnetization becomes zero, is strongly affected by the strain constraint from different oriented GaAs substrates. Our results show an elevated Tt of 350 K for MnAs films grown on GaAs (110) surface, which is attributed to the effect of strain constraint from different directions.
PACS: 68.35.Rh, 61.50.Ks, 81.15.Hi, 07.85.Qe