Investigation of exchange interactions in modulation doped magnetic semiconductor
P.V.Wadekar1*, C.W. Chang1, S. S. Guo1, Y. J. Zheng1, W. C. Hsieh1, Q. Y. Chen1, L. W. Tu1
1Physics, National Sun Yat Sen University, Kaohsiung, Taiwan
* presenting author:Paritosh Wadekar,
Attaining carrier mediated ferromagnetism in diluted magnetic semiconductors in one of the important challenges of semiconductor spintronics. To this end, we utilize the concept of modulation doping in diluted magnetic semiconductors. The band offset between the barrier (AlGaN) and the well (GaN) can be tuned so as to create a two dimension hole gas in the well. By selectively doping magnetic ions, such as manganese in the wells, we intend to create the magnetic interaction between the magnetic ions and free carriers. The electrical properties of such modulated doped structures were simulated using NextNano, while the samples were grown in a plasma assisted molecular beam epitaxy (PA-MBE) equipped with in-situ reflection high energy reflection diffraction system (RHEED). The samples are further characterized using a variety of ex-situ techniques such as X-ray diffraction (XRD) and X-ray reflectivity (XRR) for structural analysis, X-ray photoelectron spectroscopy (XPS) for chemical analysis, and magnetic and magneto-transport analysis for studying the exchange interactions

Keywords: magnetic semiconductors, modulation doping , exchange interaction