Exploration of Ti0.9Fe0.1-Ni O2 thin films as dilute magnetic semiconductors

2021 ◽  
pp. 138941
Author(s):  
Salma Waseem ◽  
Safia Anjum ◽  
Talat Zeeshan
2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
D. Venkatesan ◽  
D. Deepan ◽  
J. Ramkumar ◽  
S. Moorthy Babu ◽  
R. Dhanasekaran

CdS nanoparticles and thin films are well known for their excellent semiconducting properties. When transition metal ions are doped into the CdS, it exhibits magnetic properties in addition to semiconducting properties and they are termed as dilute magnetic semiconductors (DMSs). In this paper, we discuss the preparation of sodium bis(2-ethylhexyl) sulfonsuccinate (AOT) capped CdS nanoparticles and thin films doped with magnetic impurity Mn. Sodium bis(2-ethulexyl) sulfonsuccinate (AOT), capping agent promotes the uniform formation of nanoparticles. Optical characterizations are made using the UV-Vis spectrometer, PL, and FTIR. XRD shows the hexagonal structure of the CdS. SEM images and EDS measurements were made for the thin films. EPR shows the clear hyperfine lines corresponding to Mn2+ion in the CdS nanoparticles.


2011 ◽  
Vol 1329 ◽  
Author(s):  
Bahadir Kucukgok ◽  
Liqin Su ◽  
Elisa N. Hurwitz ◽  
Andrew Melton ◽  
Liu Zhiqiang ◽  
...  

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.


2009 ◽  
Vol 1183 ◽  
Author(s):  
Abhijit Ghosh ◽  
N. Ukah ◽  
R K Gupta ◽  
P K Kahol ◽  
K Ghosh

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.


2013 ◽  
Vol 76 (7) ◽  
pp. 751-755 ◽  
Author(s):  
Subramanian Balamurali ◽  
Rathinam Chandramohan ◽  
Marimuthu Karunakaran ◽  
Thayan Mahalingam ◽  
Padmanaban Parameswaran ◽  
...  

MRS Bulletin ◽  
2008 ◽  
Vol 33 (11) ◽  
pp. 1053-1058 ◽  
Author(s):  
J.M.D. Coey ◽  
S.A. Chambers

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.


2014 ◽  
Vol 97 (10) ◽  
pp. 3184-3191 ◽  
Author(s):  
Sivashankaran Nair Sujatha Lekshmy ◽  
Vijayam Sukumaran Nair Anitha ◽  
PuthenKadathil Vargehese Thomas ◽  
Kunjkunju Joy

2007 ◽  
Vol 1032 ◽  
Author(s):  
Ram Gupta ◽  
D. Brown ◽  
K. Ghosh ◽  
S. R. Mishra ◽  
P. K. Kahol

AbstractDilute Magnetic Semiconductors (DMS) are a rare group of promising materials that utilize both the electronic charge - a characteristic of semiconductor materials - and the electronic spin - a characteristic of magnetic materials. Oxide based DMS show promise of ferromagnetism (FM) at room temperature. It has been found that doping metal oxides such as ZnO, TiO2, and In2O3 with magnetic ions such as Fe, Co, Mn, and Cr produces DMS, which exhibit FM above room temperature. In2O3, a transparent opto-electronic material, is an interesting prospect for spintronics due to a unique combination of magnetic, electrical, and optical properties. High quality thin films of rare earth magnetic gadolinium (Gd) doped oxide-based DMS materials have been grown by pulsed laser deposition (PLD) technique on various substrates such as single crystal of sapphire (001) and quartz under suitable growth conditions of substrate temperature and oxygen pressure in the PLD chamber. The effect of rare earth magnetic doping on the structural and electro - magnetic properties of these films has been studied using Raman Spectroscopy, X-Ray Diffraction, Scanning Electron Microscopy, and Magneto - Transport. An X- ray diffraction study reveals that these films are single phase and highly oriented. Characteristic Raman peaks typical of indium oxide are observed at 496 and 627 cm−1. We have observed high magnetoresistance (∼18 %) at a relatively small field of 1.3 Tesla for the films with 10 % gadolinium. A detailed study of temperature and magnetic field dependent resistivity, magnetoresistance, and Hall Effect will be presented.


2007 ◽  
Vol 999 ◽  
Author(s):  
Deepayan Chakraborti ◽  
John T. Prater ◽  
Jagdish Narayan

AbstractSystematic studies on the epitaxial growth and the effect of n-type (Al,Ga) doping on the magnetic and electrical properties of 2.0 % Cu doped ZnO dilute magnetic semiconducting thin films deposited on c-plane sapphire single crystals by pulsed laser deposition are reported here. An decrease in more than 3 orders of magnitude in resistivity from 2×101 Ohm cm for the 2.0 % Cu doped ZnO to ~5×10-3 Ohm cm for Al and Ga codoped films is observed. This increase in conductivity does not show any effect on ferromagnetic ordering thus contradicting the claim of free carrier mediated exchange as being responsible for ferromagnetic ordering in these DMS systems. A bound magnetic polaron or F-center mediated exchange is a possible explanation for the origin of ferromagnetism in these ZnO based DMS thin films.


2020 ◽  
Vol 126 (7) ◽  
Author(s):  
Zohra Nazir Kayani ◽  
Ayesha Usman ◽  
Hina Nazli ◽  
Riffat Sagheer ◽  
Saira Riaz ◽  
...  

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