Novel Germanium-Based Magnetic Semiconductors

Abstract

Epitaxial synthesis and properties of novel Co and Mn-doped Ge magnetic semiconductors were studied. Epitaxial growth of high quality films with high doping concentrations has been stabilized by the use of two dopants. The magnetic and transport properties of the system exhibit high T(C) and large magnetoresistance effects that can be controlled systematically by the doping concentration. The maximum T(C) achieved in the semiconducting materials is approximately 270 K at a composition of Co0.12Mn0.03Ge0.85.

Review of 3D topological insulator thin‐film growth by molecular beam epitaxy and potential applications

“…Theoretical calculations suggested that by introducing magnetic impurities into a TI host lattice, ferromagnetic orders would form, the surface band would open a gap, and the massless Dirac fermion surface states thus turn into a massive region [61]. Experimentally very similar to the idea of diluted magnetic semiconductors, by doping substitutionally transition metals into conventional semiconductors (Ge [62], GaAs [63], ZnO [64], etc. ), ferromagnetic ordering was achieved in the transition-metaldoped TIs [65][66][67].…”

Magnetic MnxGe1-x Dots for Spintronics Applications

“…There is also considerable interest for transition metal doped group IV semiconductors (Miyoshi et al, 1999, Park et al, 2002, Tsui et al, 2003, D'Orazio et al, 2004, Li et al, 2005, Demidov et al, 2006, Jamet et al, 2006, Collins et al, 2008, Ogawa et al, 2009, Tsuchida et al, 2009) to the semiconductor industry, owing in part to their excellent compatibility with silicon process technology. Several transition metals -including the use of single and co-doping of elements such as Mn, Cr, Co, Fe, Co-Mn, and Fe-Mn -have been used as magnetic dopants in both Si and Ge either through blanket implantation or through in-situ doping during epitaxial growth process.…”

Enhancement of ferromagnetic properties in In1.99Co0.01O3 by additional Cu doping

“…Since the discovery of ferromagnetism in Mn-doped GaAs [1], considerable research has focused on finding new semiconductors exhibiting ferromagnetic features [2][3][4][5]. Practical applications based on such functional materials are in urgent need of ferromagnetic DMSs with Curie temperature (T c ) higher than room-temperature.…”