Abstract
We present a study of the electrical and magnetic properties of the amorphous Ge1-xMnx.DMS, with 2% ≤ x ≤ 17%, by means of SQUID magnetometry and low temperature DC measurements. The thin films were grown by physical vapour deposition at 50°C in ultrahigh vacuum. The DC electrical characterizations show that variable range hopping is the main mechanism of charge transport below room temperature. Magnetic characterization reveals that a unique and smooth magnetic transition is present in our samples, which can be attributed to ferromagnetic percolation of bound magnetic polarons.
Highlights
Diluted magnetic semiconductors (DMS) are a class of materials in which a magnetically inert host semiconductor (Ge, GaAs, CdTe or ZnSe) is doped with localized spins and carriers, either electrons or holes that are either itinerant or localized at the impurity sites
The electrical and magnetic properties of amorphous Ge1-xMnx thin films obtained through physical vapour co-deposition of Ge and Mn from solid sources have been studied by means of SQUID magnetometry and DC electrical measurements
It is shown that localization in such systems is the main physical mechanism that can account for both the electrical and magnetic properties, ruling out the presence of ferromagnetic precipitates that would have resulted in a composite system instead of a diluted magnetic semiconductor
Summary
Diluted magnetic semiconductors (DMS) are a class of materials in which a magnetically inert host semiconductor (Ge, GaAs, CdTe or ZnSe) is doped with localized spins and carriers, either electrons or holes that are either itinerant or localized at the impurity sites. This attention is due mainly to the huge variety of magnetic behaviour that is linked to the tendencies of the transition metal ions to segregate in the semiconductor host, forming nanoclusters or nanocolumns, which are themselves ferromagnetic.[2] Less work has been devoted to the study of the amorphous phase,[3,4,5,6] which represents an interesting route to circumvent the issue represented by the formation of precipitates These are very small crystallites that form when the DMS is grown at relatively high temperatures during epitaxial growth processes (typically by molecular beam epitaxy). The proposed approach will provide the possibility to extract the localization length for the confined charge carriers in such highly disordered system
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
