Room-Temperature Ferromagnetism in (Zn,Mn,Sn)As2Thin Films Applicable to InP-Based 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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Two-Dimensional [CaCl]+●e- and its strippable feasibility as an applicable electride with room temperature ferromagnetism and extremely low work function

Journal of Materials Chemistry C ◽

10.1039/d1tc04356k ◽

2021 ◽

Author(s):

Weizhen Meng ◽

Xiaoming Zhang ◽

Ying Liu ◽

Xuefang Dai ◽

HongLi Gao ◽

...

Keyword(s):

Work Function ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Two Dimensional ◽

Spintronic Devices ◽

Work Functions ◽

Application Prospects

Electrides in two-dimensional (2D) scale, especially those capture inherent magnetism and low work functions, have shown great application prospects in nanoscale spintronic devices and electronic emitters. However, searching ideal 2D...

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Coexistence of intrinsic room-temperature ferromagnetism and piezoelectricity in monolayer BiCrX3 (X = S, Se, Te)

Physical Chemistry Chemical Physics ◽

10.1039/d1cp04900c ◽

2021 ◽

Author(s):

Guang Song ◽

Chengfeng Zhang ◽

Zhengzhong Zhang ◽

Guannan Li ◽

Zhongwen Li ◽

...

Keyword(s):

Room Temperature ◽

2D Materials ◽

Room Temperature Ferromagnetism ◽

Two Dimensional ◽

Spintronic Devices ◽

Potential Applications ◽

Intrinsic Ferromagnetism

Two-dimensional (2D) materials with intrinsic ferromagnetism and piezoelectricity have received growing attention due to their potential applications in nanoscale spintronic devices. However, their applications are highly limited by the low...

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Room-Temperature Ferromagnetism and Extraordinary Hall Effect in Nanostructured Q-Carbon: Implications for Potential Spintronic Devices

ACS Applied Nano Materials ◽

10.1021/acsanm.7b00253 ◽

2018 ◽

Vol 1 (2) ◽

pp. 807-819 ◽

Cited By ~ 26

Author(s):

Anagh Bhaumik ◽

Sudhakar Nori ◽

Ritesh Sachan ◽

Siddharth Gupta ◽

Dhananjay Kumar ◽

...

Keyword(s):

Hall Effect ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Spintronic Devices ◽

Extraordinary Hall Effect

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Nearly room temperature ferromagnetism in a magnetic metal-rich van der Waals metal

Science Advances ◽

10.1126/sciadv.aay8912 ◽

2020 ◽

Vol 6 (3) ◽

pp. eaay8912 ◽

Cited By ~ 9

Author(s):

Junho Seo ◽

Duck Young Kim ◽

Eun Su An ◽

Kyoo Kim ◽

Gi-Yeop Kim ◽

...

Keyword(s):

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Van Der Waals ◽

Spin Current ◽

Perpendicular Magnetic Anisotropy ◽

Long Distance ◽

Effective Spin ◽

Experimental Realization ◽

Spintronic Devices ◽

Source Operation

In spintronics, two-dimensional van der Waals crystals constitute a most promising material class for long-distance spin transport or effective spin manipulation at room temperature. To realize all-vdW-material–based spintronic devices, however, vdW materials with itinerant ferromagnetism at room temperature are needed for spin current generation and thereby serve as an effective spin source. We report theoretical design and experimental realization of a iron-based vdW material, Fe4GeTe2, showing a nearly room temperature ferromagnetic order, together with a large magnetization and high conductivity. These properties are well retained even in cleaved crystals down to seven layers, with notable improvement in perpendicular magnetic anisotropy. Our findings highlight Fe4GeTe2 and its nanometer-thick crystals as a promising candidate for spin source operation at nearly room temperature and hold promise to further increase Tc in vdW ferromagnets by theory-guided material discovery.

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Interfacial dominated ferromagnetism in nanograined ZnO: a μSR and DFT study

Scientific Reports ◽

10.1038/srep08871 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 89

Author(s):

Thomas Tietze ◽

Patrick Audehm ◽

Yu–Chun Chen ◽

Gisela Schütz ◽

Boris B. Straumal ◽

...

Keyword(s):

Grain Boundaries ◽

Density Functional ◽

Room Temperature ◽

Volume Fraction ◽

Muon Spin ◽

Room Temperature Ferromagnetism ◽

Sample Volume ◽

Functional Theory ◽

Spintronic Devices ◽

Magnetic Ions

Abstract Diamagnetic oxides can, under certain conditions, become ferromagnetic at room temperature and therefore are promising candidates for future material in spintronic devices. Contrary to early predictions, doping ZnO with uniformly distributed magnetic ions is not essential to obtain ferromagnetic samples. Instead, the nanostructure seems to play the key role, as room temperature ferromagnetism was also found in nanograined, undoped ZnO. However, the origin of room temperature ferromagnetism in primarily non–magnetic oxides like ZnO is still unexplained and a controversial subject within the scientific community. Using low energy muon spin relaxation in combination with SQUID and TEM techniques, we demonstrate that the magnetic volume fraction is strongly related to the sample volume fraction occupied by grain boundaries. With molecular dynamics and density functional theory we find ferromagnetic coupled electron states in ZnO grain boundaries. Our results provide evidence and a microscopic model for room temperature ferromagnetism in oxides.

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Structural and Magnetic Characterization of MOCVD Grown GaMnN and GaFeN Nanostructures

MRS Proceedings ◽

10.1557/proc-0959-m17-24 ◽

2006 ◽

Vol 959 ◽

Author(s):

Shalini Gupta ◽

Hun Kang ◽

Matthew H. Kane ◽

Eun Hyun Park ◽

Ian T. Ferguson

Keyword(s):

Transition Metals ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Magnetic Characterization ◽

Hysteresis Behavior ◽

Spintronic Devices ◽

Magnetization Study

ABSTRACTThe growth of Ga1-xMnxN and Ga1-xFexN nanostructures was carried out by MOCVD. Introduction of transition metals (TM) Mn and Fe in GaN nanostructures enhanced the nucleation of the nanostructures resulting in reduced lateral dimensions and increased nanostructure density. The Ga1-xMnxN nanostructures showed hysteresis behavior at 5K. Room temperature ferromagnetism was obtained in the Ga1-xFexN nanostructures unlike its bulk counterpart. This paper presents the growth and magnetization study of Ga1-xTMxN nanostructures. These structures could be used to enhance the efficiency of spintronic devices.

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Nodal-Loop Half Metallicity in Two-Dimensional Fe4N2 Pentagon Crystal with Room-Temperature Ferromagnetism

Nanoscale ◽

10.1039/d1nr06033c ◽

2021 ◽

Author(s):

Kai Zhang ◽

Minglong Chen ◽

Dayong Wang ◽

Haifeng Lv ◽

Xiaojun Wu ◽

...

Keyword(s):

High Speed ◽

Room Temperature ◽

2D Materials ◽

Room Temperature Ferromagnetism ◽

Two Dimensional ◽

Half Metallicity ◽

Spintronic Devices ◽

Low Dissipation ◽

Spin Polarized ◽

Band Crossing

Two-dimensional (2D) materials with fully spin-polarized nodal-loop band crossing are a class of topological magnetic materials, holding promise for high-speed low-dissipation spintronic devices. Recently, several 2D nodal-loop materials have been...

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Room Temperature Ferromagnetism in Spin-coated Anatase- and Rutile- Ti1-x Mx O2 ( M= Fe, Mn, Co) Films

MRS Proceedings ◽

10.1557/proc-1201-h10-07 ◽

2009 ◽

Vol 1201 ◽

Author(s):

Danilo Barrionuevo ◽

Surinder P Singh ◽

Maharaj S. Tomar

Keyword(s):

Metal Ion ◽

Room Temperature ◽

Diluted Magnetic Semiconductors ◽

Magnetic Semiconductors ◽

Room Temperature Ferromagnetism ◽

Sol Gel ◽

Ion Concentration ◽

Spintronic Devices ◽

Diluted Magnetic ◽

Quartz Substrates

AbstractDiluted magnetic semiconductors (DMS) have been explored extensively, because of their potential application in spintronic devices. We studied the structural optical and magnetic properties of Ti1-xMxO2 (M= Fe, Mn, Co; x = 0.00, 0.05, 0.08, 0.10, 0.15, 0.20, 0.25, 0.30), thin films by sol-gel process and deposited using spin coating on Pt (Pt/Ti/SiO2/Si) and quartz substrates. X-ray diffraction studies and Raman spectroscopy reveal anatase and rutile phases of the synthesized films when annealed at 500 and 10000 C, respectively. Optical transmission measurements show high degree of transparency that decreases with increase in transition metal ion concentration. The films show room temperature ferromagnetism, suggesting their potential in spin based heterojunction devices.

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