Magneto-transport Properties of Cobalt doped Indium Oxide Dilute Magnetic Semiconductors

AbstractRecently, oxide-based dilute magnetic semiconductors (DMS) have attracted an immense research interest to the scientists due to the possibility of inducing room temperature ferromagnetism and potential uses in novel spintronic devices. In2O3, a transparent opto-electronic material, is an interesting prospect for spintronics due to its unique combination of magnetic, electrical, and optical properties. High quality thin films of Co-doped In2O3 DMS were grown on quartz substrates using pulsed laser deposition technique. All the films have been characterized using different techniques such as x-ray diffraction, Raman spectroscopy, optical transmission spectroscopy, electrical resistivity, and Hall Effect measurement. The effect of growth temperature and oxygen pressure on the electrical, magnetic, and optical properties of these films have been studied in detail. The optical transparency in all the films is high. It has been observed that the optical transparency depends on growth temperature and oxygen pressure. The electrical parameters such as resistivity, carrier concentration, and mobility strongly depend on both oxygen pressure and growth temperature. The films grown at low temperature are semiconducting in nature while the films grown at high temperature are metallic. Detailed temperature and magnetic field dependent resistivity, magnetoresistance, and Hall effect data will be presented. This work is supported by Research Corporation (award number CC6166).

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THE GROWTH AND CHARACTERIZATION OF ROOM TEMPERATURE FERROMAGNETIC WIDEBAND-GAP MATERIALS FOR SPINTRONIC APPLICATIONS

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156406003825 ◽

2006 ◽

Vol 16 (02) ◽

pp. 515-543

Author(s):

MATTHEW H. KANE ◽

MARTIN STRASSBURG ◽

WILLIAM E. FENWICK ◽

ALI ASGHAR ◽

IAN T. FERGUSON

Keyword(s):

Room Temperature ◽

Magnetic Semiconductors ◽

Room Temperature Ferromagnetism ◽

Dilute Magnetic Semiconductors ◽

Chemical Vapor ◽

Wide Bandgap ◽

Organic Chemical ◽

Ferromagnetic Behavior ◽

Spintronic Devices

Wide-bandgap dilute magnetic semiconductors (DMS), such as transition-metal doped ZnO and GaN , have gained attention for use in spintronic devices because of predictions and experimental reports of room temperature ferromagnetism which may enable their use in spintronic devices. However, there has been some debate over the source of ferromagnetism in these materials. This paper focuses on the high quality growth of wide bandgap DMS, and the characterization of Zn 1-x Mn x O produced by melt-growth techniques and Ga 1-x Mn x N grown by metal organic chemical vapor deposition (MOCVD). High resolution X-ray diffraction results revealed no second phases in either the ZnO crystals or the GaN films. Undoped as-grown, bulk crystals of Zn 1-x Mn x O and Zn 1-x Co x O crystals are shown to be paramagnetic at all temperatures. In contrast, the Ga 1-x Mn x N films showed ferromagnetic behavior at room temperature under optimum growth conditions. Experimental identification of the Mn ion charge state and the presence of bands in the bandgap of GaN are investigated by optical spectroscopy and electron spin paramagnetic resonance (EPR). It is shown that the broadening of states in the Mn 3d shell scaled with Mn concentration, and that optical transitions due to this band correlated with the strong ferromagnetism in these samples. However, this band disappeared with an increase in free electron concentration provided by either annealing or doping. Raman studies of Ga 1-x Mn x N revealed two predominant Mn -related modes featured with increasing concentration, a broad disorder related structure at 300cm-1 and a sharper peak at 669cm-1 This works show that the development of practical ferromagnetic wide bandgap DMS materials for spintronic applications will require both the lattice site introduction of Mn as well as careful control of the background defect concentration to optimize these materials.

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A Review on Chemical Synthesis, Characterization and Optical Properties of Nanocrystalline Transition Metal Doped Dilute Magnetic Semiconductors

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.201.103 ◽

2013 ◽

Vol 201 ◽

pp. 103-129 ◽

Cited By ~ 5

Author(s):

Tokeer Ahmad ◽

Sarvari Khatoon ◽

Ruby Phul

Keyword(s):

Optical Properties ◽

Transition Metal ◽

Magnetic Semiconductors ◽

Room Temperature Ferromagnetism ◽

Magnetic Semiconductor ◽

Dilute Magnetic Semiconductors ◽

Exchange Interactions ◽

Transition Metal Ions ◽

Modern Technology ◽

Metal Doped

Nanomaterials have fascinated researchers in recent years because these materials exhibit unusual optical, magnetic and electrical properties as compared to their bulk counterparts. Incorporating impurity ions into a semiconducting host to extend its properties has been one of the most important techniques that paved the way for the modern technology based on spintronic devices. Over the past few years, oxide based dilute magnetic semiconductors (DMSs) have gained remarkable interest due to the possibility of inducing room temperature ferromagnetism. This review describes the experimental developments and optical properties of oxide based DMSs, including the recent results on ZnO, CdO and In2O3 based systems. Optical properties of transition metal (TM)-doped ZnO, CdO and In2O3 dilute magnetic semiconductor nanoparticles show red shift in energy band gaps. Such types of phenomena are attributed to sp-d exchange interactions between band electrons and localized d-electrons of the substituted transition metal ions. Table of Contents

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Review on Available Theoretical Models for Room Temperature Ferromagnetism in Dilute Magnetic Semiconductors

Journal of Nano- and Electronic Physics ◽

10.21272/jnep.11(3).03039 ◽

2019 ◽

Vol 11 (3) ◽

pp. 03039-1-03039-3 ◽

Cited By ~ 1

Author(s):

Rana Mukherji ◽

◽

Vishal Mathur ◽

Keyword(s):

Room Temperature ◽

Magnetic Semiconductors ◽

Room Temperature Ferromagnetism ◽

Dilute Magnetic Semiconductors ◽

Theoretical Models

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Room temperature ferromagnetism in III–V and II–IV–V2 dilute magnetic semiconductors

Physica B Condensed Matter ◽

10.1016/j.physb.2005.11.124 ◽

2006 ◽

Vol 374-375 ◽

pp. 430-432 ◽

Cited By ~ 9

Author(s):

V.G. Storchak ◽

D.G. Eshchenko ◽

H. Luetkens ◽

E. Morenzoni ◽

R.L. Lichti ◽

...

Keyword(s):

Room Temperature ◽

Magnetic Semiconductors ◽

Room Temperature Ferromagnetism ◽

Dilute Magnetic Semiconductors

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Optical properties and functions of dilute magnetic semiconductors

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/16/48/009 ◽

2004 ◽

Vol 16 (48) ◽

pp. S5541-S5548 ◽

Cited By ~ 53

Author(s):

K Ando ◽

H Saito ◽

V Zayets ◽

M C Debnath

Keyword(s):

Optical Properties ◽

Magnetic Semiconductors ◽

Dilute Magnetic Semiconductors

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Seebeck and Spin Seebeck effect in Gd-doped GaN thin films for Thermoelectric Devices and Applications

MRS Proceedings ◽

10.1557/opl.2011.1236 ◽

2011 ◽

Vol 1329 ◽

Author(s):

Bahadir Kucukgok ◽

Liqin Su ◽

Elisa N. Hurwitz ◽

Andrew Melton ◽

Liu Zhiqiang ◽

...

Keyword(s):

Thin Films ◽

Low Power ◽

Room Temperature ◽

Magnetic Semiconductors ◽

Dilute Magnetic Semiconductors ◽

Seebeck Effect ◽

Ferromagnetic Behavior ◽

Successful Development ◽

Spintronic Devices ◽

Spin Seebeck Effect

ABSTRACTGaN-based dilute magnetic semiconductors (DMS) have recently been investigated for use in spintronic devices. In particular, Gd-doped GaN has shown very promising room temperature ferromagnetic behavior and potential for use in spintronics applications. III-Nitride materials have recently had their thermoelectric properties investigated; however this work has not been extended to Nitride-based DMS. Understanding the spin-calorimetric characteristics of GaN-based DMS is important to the successful development of low-power spintronic devices. In this paper the Seebeck and spin-Seebeck effect in MOCVD grown Gd-doped GaN (Gd: GaN) are investigated.

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Optical Properties and Ferromagnetism of Fe and Ni Co-doped ZnO Dilute Magnetic Semiconductors

Chinese Journal of Luminescence ◽

10.3788/fgxb20143502.0178 ◽

2014 ◽

Vol 35 (2) ◽

pp. 178-183

Author(s):

魏智强 WEI Zhi-qiang ◽

张玲玲 ZHANG Ling-ling ◽

武晓娟 WU Xiao-juan ◽

吴永富 WU Yong-fu ◽

王璇 WANG Xuan

Keyword(s):

Optical Properties ◽

Magnetic Semiconductors ◽

Dilute Magnetic Semiconductors ◽

Doped Zno ◽

Co Doped

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Effect of Partial Oxygen Pressure on Structural, Electrical, and Magneto transport Properties of Cobalt Doped Indium Oxide Thin Films

MRS Proceedings ◽

10.1557/proc-1183-ff06-15 ◽

2009 ◽

Vol 1183 ◽

Author(s):

Abhijit Ghosh ◽

N. Ukah ◽

R K Gupta ◽

P K Kahol ◽

K Ghosh

Keyword(s):

Thin Films ◽

Transport Properties ◽

Indium Oxide ◽

Oxygen Pressure ◽

Magnetic Semiconductors ◽

Growth Parameters ◽

Dilute Magnetic Semiconductors ◽

Partial Oxygen Pressure ◽

Magneto Resistance ◽

Partial Oxygen

AbstractDilute magnetic semiconductors are ferromagnetic semiconductors recently discovered in nitride and oxide semiconductors by incorporating a small percentage of magnetic atoms into the semiconductors host. Recently it is reported that the structural and electrical properties of pure indium oxide can be modified by growth parameters. In this paper we investigate magneto-transport properties of Co-doped In2O3 dilute magnetic semiconductors thin films grown on sapphire and quartz substrates using pulsed laser deposition technique. The effect of partial oxygen pressure on structural, electrical, optical, and magneto-transport properties was discussed in details. The crystallinity of the films largely depends on growth temperature. Magneto-transport properties such as temperature dependent resistivity and magneto-resistance were found to be very sensitive to the micro-structural properties such as crystalinity as well as oxygen defect. The electrical carrier density of the films depends on oxygen pressure and a change of two orders of magnitude is observed. Depending on growth parameters, both positive and negative magneto-resistance is observed. Optical band-gap seems to vary with the growth partial oxygen pressure.

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Oxide Dilute Magnetic Semiconductors—Fact or Fiction?

MRS Bulletin ◽

10.1557/mrs2008.225 ◽

2008 ◽

Vol 33 (11) ◽

pp. 1053-1058 ◽

Cited By ~ 137

Author(s):

J.M.D. Coey ◽

S.A. Chambers

Keyword(s):

Thin Films ◽

High Temperature ◽

Magnetic Semiconductors ◽

Bulk Material ◽

Room Temperature Ferromagnetism ◽

Magnetic Moments ◽

Dilute Magnetic Semiconductors ◽

Double Exchange ◽

Secondary Phases ◽

Solid State Mater

AbstractMagnetism in oxides was thought to be well-understood in terms of localized magnetic moments and double-exchange or superexchange rules. This understanding was shaken by the publication of an article in 2001 stating that thin films of anatase TiO2 with only 7 at.% Co substitution had a Curie point in excess of 400 K [Matsumoto et al., Science291, 854 (2001)]. Room-temperature ferromagnetism had previously been predicted for p-type ZnO with 5 at.% Mn [Dietl et al., Science287, 1019 (2000)]. A flood of reports of thin films and nanoparticles of new oxide “dilute magnetic semiconductors” (DMSs) followed, and high-temperature ferromagnetism has been reported for other systems with no 3dcations. The expectation that these materials would find applications in spintronics motivated research in this area. Unfortunately, the data are plagued by instability and a lack of reproducibility. In many cases, the ferromagnetism can be explained by uncontrolled secondary phases; it is absent in well-crystallized films and bulk material. However, it appears that some form of high-temperature ferromagnetism can result from defects present in the oxide films [Coey, Curr. Opin. Solid State Mater. Sci.10, 83 (2007); Chambers, Surf. Sci. Rep.61, 345 (2006)], although they are not DMSs as originally envisaged.

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