Carrier-controlled ferromagnetism in transparent oxide semiconductors

Abstract

The search for an ideal magnetic semiconductor with tunable ferromagnetic behaviour over a wide range of doping or by electrical gating is being actively pursued as a major step towards realizing spin electronics. A magnetic semiconductor having a high Curie temperature, capable of independently controlled carrier density and magnetic doping, is crucial for developing spin-based multifunctional devices. Cr-doped In(2)O(3) is such a unique system, where the electrical and magnetic behaviour-from ferromagnetic metal-like to ferromagnetic semiconducting to paramagnetic insulator-can be controllably tuned by the defect concentration. An explicit dependence of magnetic interaction leading to ferromagnetism on the carrier density is shown. A carrier-density-dependent high Curie temperature of 850-930 K has been measured, in addition to the observation of clear magnetic domain structures in these films. Being optically transparent with the above optimal properties, Cr-doped In(2)O(3) emerges as a viable candidate for the development of spin electronics.

Carrier-mediated nonlocal ferromagnetic coupling between local magnetic polarons in Fe-doped In2O3and Co-doped ZnO

“…[7][8][9][10][11] Commonly invoked host materials include ZnO, TiO 2 , In 2 O 3 and SnO 2 . Despite the progress in developing oxide DMSs, the underlying mechanism for ferromagnetic ordering is still under active debate.…”

Study The Electrical Properties of Co/TiO2 Multilayer Thin Films

“…It is noteworthy to mention that Co/TiO 2 This results the decrement of conductivity. It is also observed that higher thickness Co/TiO 2 thin films show lower conductivity compare to the lower thickness one for both as-deposited and annealed.…”

“…Transparent magnetic oxides have a high potentiality for fabricating future multifunctional spintronic devices according to the various technological reports and roadmaps [1][2][3][4][5]. One of the approaches in achieving this goal is the doping of transition magnetic (TM) material into transparent oxide [4][5][6].…”

“…One of the approaches in achieving this goal is the doping of transition magnetic (TM) material into transparent oxide [4][5][6]. In several cases, TM doped oxide such as Co doped ZnO, TiO 2 and SnO 2 etc. shows ferromagnetism at room temperature [5][6][7][8][9][10][11][12].…”

Different magnetic properties of rhombohedral and cubic Ni2+ doped indium oxide nanomaterials

“…6 To endow In 2 O 3 with better or special properties, they are often doped by transition metal (TM) ions in order to introduce ferromagnetisms to non-magnetic In 2 O 3 , which is called as diluted magnetic semiconductor (DMSs) and potentially applied in transparent spintronic devices. [7][8][9][10][11][12][13] For example, Farvid et al 14 prepared paramagnetic Cr doped C-In 2 O 3 nanocrystals while Singhal et al 15 synthesized ferromagnetic Fe doped C-In 2 O 3 nanoparticles. In addition, Philip et al 7 could control ferromagnetisms of Cr doped C-In 2 O 3 films by tuning carrier density.…”