Magnetic and Electronic Properties of Weyl Semimetal Co2MnGa Thin Films

Magnetic Weyl semimetals are newly discovered quantum materials with the potential for use in spintronic applications. Of particular interest is the cubic Heusler compound Co2MnGa due to its inherent magnetic and topological properties. This work presents the structural, magnetic and electronic properties of magnetron co-sputtered Co2MnGa thin films, with thicknesses ranging from 10 to 80 nm. Polarized neutron reflectometry confirmed a uniform magnetization through the films. Hard x-ray photoelectron spectroscopy revealed a high degree of spin polarization and localized (itinerant) character of the Mn d (Co d) valence electrons and accompanying magnetic moments. Further, broadband and field orientation-dependent ferromagnetic resonance measurements indicated a relation between the thickness-dependent structural and magnetic properties. The increase of the tensile strain-induced tetragonal distortion in the thinner films was reflected in an increase of the cubic anisotropy term and a decrease of the perpendicular uniaxial term. The lattice distortion led to a reduction of the Gilbert damping parameter and the thickness-dependent film quality affected the inhomogeneous linewidth broadening. These experimental findings will enrich the understanding of the electronic and magnetic properties of magnetic Weyl semimetal thin films.

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Effects of Perpendicular Magnetic Field Annealing on the Structural and Magnetic Properties of [Co/Ni]2/PtMn Thin Films

Magnetochemistry ◽

10.3390/magnetochemistry7030038 ◽

2021 ◽

Vol 7 (3) ◽

pp. 38

Author(s):

Roshni Yadav ◽

Chun-Hsien Wu ◽

I-Fen Huang ◽

Xu Li ◽

Te-Ho Wu ◽

...

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Magnetic Properties ◽

Photoelectron Spectroscopy ◽

Perpendicular Magnetic Field ◽

Face Centered Cubic ◽

Lattice Image ◽

X Ray ◽

Field Annealing ◽

Face Centered

In this study, [Co/Ni]2/PtMn thin films with different PtMn thicknesses (2.7 to 32.4 nm) were prepared on Si/SiO2 substrates. The post-deposition perpendicular magnetic field annealing (MFA) processes were carried out to modify the structures and magnetic properties. The MFA process also induced strong interlayer diffusion, rendering a less sharp interface between Co and Ni and PtMn layers. The transmission electron microscopy (TEM) lattice image analysis has shown that the films consisted of face-centered tetragonal (fct) PtMn (ordered by MFA), body-centered cubic (bcc) NiMn (due to intermixing), in addition to face-centered cubic (fcc) Co, Ni, and PtMn phases. The peak shift (2-theta from 39.9° to 40.3°) in X-ray diffraction spectra also confirmed the structural transition from fcc PtMn to fct PtMn after MFA, in agreement with those obtained by lattice images in TEM. The interdiffusion induced by MFA was also evidenced by the depth profile of X-ray photoelectron spectroscopy (XPS). Further, the magnetic properties measured by vibrating sample magnetometry (VSM) have shown an increased coercivity in MFA-treated samples. This is attributed to the presence of ordered fct PtMn, and NiMn phases exchange coupled to the ferromagnetic [Co/Ni]2 layers. The vertical shift (Mshift = −0.03 memu) of the hysteresis loops is ascribed to the pinned spins resulting from perpendicular MFA processes.

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Ionic Distribution and Related Electronic Properties in VxFe3-xO4 Thin Films Studied by Using Mössbauer and X-ray Photoelectron Spectroscopy

Journal of the Korean Physical Society ◽

10.3938/jkps.53.695 ◽

2008 ◽

Vol 53 (2) ◽

pp. 695-699 ◽

Cited By ~ 2

Author(s):

Jae Yun Park ◽

Jung Han Lee ◽

Kwang Joo Kim

Keyword(s):

Thin Films ◽

Electronic Properties ◽

Photoelectron Spectroscopy ◽

X Ray ◽

Ionic Distribution

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A perspective on the magnetism of alkanethiol-coated gold thin films

Canadian Journal of Chemistry ◽

10.1139/cjc-2018-0233 ◽

2018 ◽

Vol 96 (11) ◽

pp. 985-991 ◽

Cited By ~ 1

Author(s):

Pengcheng Dong ◽

Simon Trudel

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Magnetic Moments ◽

Self Assembled Monolayers ◽

Electronic And Magnetic Properties ◽

Ferromagnetic Behaviour ◽

Weak Magnetism ◽

Assembled Monolayers ◽

Gold Thin Films ◽

Chain Lengths

Intriguing ferromagnetic behaviour has been reported in gold thin films — a diamagnetic material in the bulk — wherein large magnetic moments and uncommon anisotropy are often hallmark features. The tuning of the electronic and magnetic properties by the presence of molecular self-assembled monolayers has been proposed. In this work, we present the study of the magnetism of a wide collection of alkanethiols of differing chain lengths coated on Au. We find no or only very weak magnetism, casting doubt on the universality and reproducibility of this phenomenon.

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ELECTRONIC STRUCTURES AND REORIENTATION OF PERPENDICULAR MAGNETIC ANISOTROPY OF Co/Au(111) and Co/Pd(111)

Surface Review and Letters ◽

10.1142/s0218625x0200307x ◽

2002 ◽

Vol 09 (02) ◽

pp. 865-869

Author(s):

M. SAWADA ◽

K. HAYASHI ◽

A. KAKIZAKI

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Binding Energy ◽

Film Thickness ◽

Magnetic Anisotropy ◽

Photoelectron Spectroscopy ◽

Electronic Structures ◽

Perpendicular Magnetic Anisotropy ◽

Magnetization Direction ◽

Electronic And Magnetic Properties

We have investigated electronic and magnetic properties of Co thin films epitaxially grown on Au(111) and Pd(111) substrates by spin- and angle-resolved photoelectron spectroscopy. In the Co/Au(111) system, the magnetization direction of Co changes from perpendicular to parallel to the surface at about 6 ML. The origin of the reorientation is qualitatively explained by the increasing contribution of Co 3d orbitals perpendicular to the surface. In the Co/Pd(111) system, the reorientation of the magnetization direction occurs at about 4 ML, the origin of which is explained as being due to the contribution of the upper Λ3 band of Co with increase of film thickness as in the case of the Co/Au(111) system. The stronger hybridization between Co 3d and Pd 4d states in the Co/Pd(111) system causes larger binding energy shifts of the Λ3 states than in the Co/Au(111) system.

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Electronic properties and bonding in ZrHx thin films investigated by valence-band x-ray photoelectron spectroscopy

Physical Review B ◽

10.1103/physrevb.96.195103 ◽

2017 ◽

Vol 96 (19) ◽

Cited By ~ 5

Author(s):

Martin Magnuson ◽

Susann Schmidt ◽

Lars Hultman ◽

Hans Högberg

Keyword(s):

Thin Films ◽

Electronic Properties ◽

Valence Band ◽

Photoelectron Spectroscopy ◽

X Ray

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Magnetic Properties of Amorphous Fe2O3-R2O3 (R=La, Gd and Tb) Thin Films Fabricated by Sputtering Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.39-40.207 ◽

2008 ◽

Vol 39-40 ◽

pp. 207-212 ◽

Cited By ~ 6

Author(s):

Hirofumi Akamatsu ◽

Shunsuke Murai ◽

Koji Fujita ◽

Katsuhisa Tanaka

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Spin Glasses ◽

Magnetic Moments ◽

Rare Earth Ions ◽

Aging Effects ◽

Glass Substrates ◽

Radio Frequency Sputtering ◽

Magnetic Aging ◽

Temperature Dependences

Amorphous oxide thin films of Fe2O3-R2O3 (R = La, Gd and Tb) systems have been deposited on silica glass substrates by using a radio frequency sputtering method, and magnetic properties of the thin films have been examined. The Fe2O3-La2O3 thin films exhibit cusp-like maxima of dc magnetic susceptibility in their temperature dependences as well as magnetic aging and memory effects characteristic of typical spin glasses. For Fe2O3-Gd2O3 and Fe2O3-Tb2O3 systems, magnetic moments of iron ions take part in formation of a spin glass state, as indicated by the magnetic aging effects, while those of rare-earth ions remain to be in a paramagnetic state even at very low temperatures.

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Crystal structures and magnetic properties of Fe–N thin films deposited by dc magnetron sputtering

Powder Diffraction ◽

10.1154/1.1814980 ◽

2004 ◽

Vol 19 (4) ◽

pp. 352-355 ◽

Cited By ~ 6

Author(s):

Wei Tao Zheng ◽

Xin Wang ◽

Xianggui Kong ◽

Hongwei Tian ◽

Shansheng Yu ◽

...

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Magnetron Sputtering ◽

Crystal Structures ◽

Photoelectron Spectroscopy ◽

Quantum Interference ◽

Flow Ratio ◽

Dc Magnetron Sputtering ◽

X Ray ◽

Glass Substrates

Fe–N thin films were deposited on glass substrates by dc magnetron sputtering under various Ar∕N2 discharge conditions. Crystal structures and elemental compositions of the films were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. Magnetic properties of the films were measured using a superconducting quantum interference device magnetometer. Films deposited at different N2∕(Ar+N2) flow ratios were found to have different crystal structures and different nitrogen contents. When the flow ratios were 60%, 50%, and 30%, a nonmagnetic single-phase FeN was formed in the films. At the flow ratio of 10%, two crystal phases of γ′-Fe4N and ε-Fe3N were detected. When the flow ratio reduced to 5%, a mixture of α-Fe, ε-Fe3N, FeN0.056, and α″-Fe16N2 phases was obtained. The value of saturation magnetization for the mixture was found to be larger than that of pure Fe.

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Hole Doping Through Indium Intercalation into Copper Phthalocyanine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.802.273 ◽

2013 ◽

Vol 802 ◽

pp. 273-278 ◽

Cited By ~ 1

Author(s):

Anuchit Jaruvanawat ◽

Pakorn Prajuabwan ◽

Sunit Rojanasuwan ◽

Annop Chanhom ◽

Adirek Rangkasikorn ◽

...

Keyword(s):

Thin Films ◽

Electronic Properties ◽

Photoelectron Spectroscopy ◽

Copper Phthalocyanine ◽

High Vacuum ◽

Hole Transport ◽

Hole Doping ◽

Silicon Substrates ◽

X Ray ◽

Evaporation Technique

A blend of molecular acceptor and molecular donor made of Copper Phthalocyanine (CuPc) and Indium in various ratios were evaporated in high vacuum on to intrinsic silicon substrates by using vacuum thermal co-evaporation technique. Electronic properties of In-doped CuPc thin films have been examined by X-ray photoelectron spectroscopy (XPS). The results obtained by XPS suggests that In-doped CuPc is a hole transport material.

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Effect of Sputtering Input Power of Co on Structure and Magnetic Properties of Fe-Co-N Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.635 ◽

2009 ◽

Vol 79-82 ◽

pp. 635-638 ◽

Cited By ~ 1

Author(s):

Xin Wang ◽

Hui Jia ◽

Wei Tao Zheng ◽

Wei Xu ◽

Bei Hong Long

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Photoelectron Spectroscopy ◽

Quantum Interference ◽

Input Power ◽

Superconducting Quantum Interference Device ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Composition Structure

Fe-Co-N thin films with various Co content were synthesized on Si (111) substrate using facing-target magnetron sputtering by changing sputtering input power on Co target. During deposition, the input power on Fe target was kept at 160 W. The composition, structure, and magnetic properties were examined by X-ray photoelectron spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and superconducting quantum interference device. XRD and TEM investigations showed that at lower input power of 11.2 W on Co target, the phases in the film were -(Fe,Co)4N and Co3N. Increasing sputtering input power, the content of Co in the film increased. At input power of 14 W, film contained -(Fe,Co)8N phase was produced which exhibited higher saturation magnetization (252.85 Am2/kg) and lower value of coercivity (3.66 kAm-1), corresponded to the 12% content of Co in the film.

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