Structural and paramagnetic properties of dilute Ga1-xMnxN

Article

关键词: ABSORPTION FINE-STRUCTURE;    VAPOR-PHASE EPITAXY;    TEMPERATURE FERROMAGNETISM;    ROOM-TEMPERATURE;    LOCAL-STRUCTURE;    SPECTROSCOPIC ELLIPSOMETRY;    WURTZITE (GA,MN)N;    SEMICONDUCTORS;    MN;    GAN;   

DOI  :  10.1103/PhysRevB.81.235210

来源: SCIE

【 摘 要 】

Systematic investigations of the structural and magnetic properties of single crystal Ga1-xMnxN films grown by metal organic vapor phase epitaxy are presented. High-resolution transmission electron microscopy, synchrotron x-ray diffraction, and extended x-ray absorption fine structure studies do not reveal any crystallographic phase separation and indicate that Mn occupies Ga-substitutional sites in the Mn concentration range up to 1%. The magnetic properties as a function of temperature, magnetic field and its orientation with respect to the c axis of the wurtzite structure can be quantitatively described by the paramagnetic theory of an ensemble of noninteracting Mn3+ ions in the relevant crystal field, a conclusion consistent with the x-ray absorption near edge structure analysis. A negligible contribution of Mn in the 2+ charge state points to a low concentration of residual donors in the studied films. Studies on modulation-doped p-type Ga1-xMnxN/(Ga, Al)N: Mg heterostructures do not reproduce the high-temperature robust ferromagnetism reported recently for this system.

【 授权许可】

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