Photoelectron spectroscopy and diffraction have been used to investigate structural changes during the annealing process of Ga1-xMn xAs samples. Hard x-ray radiation helped in observing photoelectron core-level spectra and electron diffraction from the bulk underlying the oxidized surface layer. High electron-energy resolution enabled us to separate the components due to substitutional and interstitial Mn atoms in the intrinsic Mn 2p3/2 photoemission profile, resulting in two peaks at 638.8 and 639.5 eV binding energy, respectively. The peaks display the known characteristic behavior after annealing, that is, an almost complete reduction of the interstitial component and preservation of the substitutional component. In the photoelectron diffraction, a sensitivity of high-energy polar plots to the incorporation sites of photoemitting atoms into the atomic lattice has been shown. As a consequence, the experimental polar plots from substitutional and interstitial Mn atoms, which are supported theoretically, show characteristic features that provide structural information. From the similarities and differences of the polar plots for Mn and Ga, we have confirmed the assignment of components within the intrinsic part of the photoemission Mn 2p3/2 signal suggested by photoelectron spectroscopy.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Jun 15 2011|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics