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Title: Growth, structural, and magnetic properties of single-crystal full-Heusler Co2TiGe thin films

Abstract

This paper presents the growth, structural characterization, and measurement of magnetic properties of Co2TiGe thin films grown by molecular beam epitaxy on insulating MgO (001) substrates and conductive lattice matched InAlAs/InGaAs/InAlAs epitaxial layers grown on n-InP (001) substrates. A GdAs diffusion barrier was used to minimize interfacial reactions during Co2TiGe growth on InAlAs. The surface morphology, structural quality, and magnetic behavior were examined by reflection high-energy electron diffraction, scanning tunneling microscopy, X-ray diffraction, and superconducting quantum interference device magnetometry. The results reveal high quality Co2TiGe thin films with a saturation magnetization of ~1.8 μB/formula unit and a Curie temperature of ~375 K. Finally, the magnetic easy axis was found to lie in the [110] direction but magnetometry also reveals that there is only a small difference in energy between the [110] and [010] magnetization directions.

Authors:
ORCiD logo [1];  [1]; ORCiD logo [1];  [1];  [2]; ORCiD logo [1]; ORCiD logo [2];  [3]
  1. Univ. of California, Santa Barbara, CA (United States). Materials Dept.
  2. Univ. of California, Santa Barbara, CA (United States). Dept. of Electrical and Computer Engineering
  3. Univ. of California, Santa Barbara, CA (United States). Materials Dept. Dept. of Electrical and Computer Engineering
Publication Date:
Research Org.:
Univ. of California, Santa Barbara, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)
OSTI Identifier:
1465336
Alternate Identifier(s):
OSTI ID: 1366557
Grant/Contract Number:  
SC0014388; DMR 11–21053
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 121; Journal Issue: 21; Journal ID: ISSN 0021-8979
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; scanning tunneling microscopy; thin film growth; carbon dioxide; crystal structure; reflection high energy electron diffraction; superconducting quantum interference devices; magnetic films; epitaxy

Citation Formats

Logan, J. A., Brown-Heft, T. L., Harrington, S. D., Wilson, N. S., McFadden, A. P., Rice, A. D., Pendharkar, M., and Palmstrøm, C. J.. Growth, structural, and magnetic properties of single-crystal full-Heusler Co2TiGe thin films. United States: N. p., 2017. Web. https://doi.org/10.1063/1.4984311.
Logan, J. A., Brown-Heft, T. L., Harrington, S. D., Wilson, N. S., McFadden, A. P., Rice, A. D., Pendharkar, M., & Palmstrøm, C. J.. Growth, structural, and magnetic properties of single-crystal full-Heusler Co2TiGe thin films. United States. https://doi.org/10.1063/1.4984311
Logan, J. A., Brown-Heft, T. L., Harrington, S. D., Wilson, N. S., McFadden, A. P., Rice, A. D., Pendharkar, M., and Palmstrøm, C. J.. Mon . "Growth, structural, and magnetic properties of single-crystal full-Heusler Co2TiGe thin films". United States. https://doi.org/10.1063/1.4984311. https://www.osti.gov/servlets/purl/1465336.
@article{osti_1465336,
title = {Growth, structural, and magnetic properties of single-crystal full-Heusler Co2TiGe thin films},
author = {Logan, J. A. and Brown-Heft, T. L. and Harrington, S. D. and Wilson, N. S. and McFadden, A. P. and Rice, A. D. and Pendharkar, M. and Palmstrøm, C. J.},
abstractNote = {This paper presents the growth, structural characterization, and measurement of magnetic properties of Co2TiGe thin films grown by molecular beam epitaxy on insulating MgO (001) substrates and conductive lattice matched InAlAs/InGaAs/InAlAs epitaxial layers grown on n-InP (001) substrates. A GdAs diffusion barrier was used to minimize interfacial reactions during Co2TiGe growth on InAlAs. The surface morphology, structural quality, and magnetic behavior were examined by reflection high-energy electron diffraction, scanning tunneling microscopy, X-ray diffraction, and superconducting quantum interference device magnetometry. The results reveal high quality Co2TiGe thin films with a saturation magnetization of ~1.8 μB/formula unit and a Curie temperature of ~375 K. Finally, the magnetic easy axis was found to lie in the [110] direction but magnetometry also reveals that there is only a small difference in energy between the [110] and [010] magnetization directions.},
doi = {10.1063/1.4984311},
journal = {Journal of Applied Physics},
number = 21,
volume = 121,
place = {United States},
year = {2017},
month = {6}
}

Works referenced in this record:

Testing epitaxial Co1.5Fe1.5Ge(001) electrodes in MgO-based magnetic tunnel junctions
journal, June 2014

  • Neggache, A.; Hauet, T.; Bertran, F.
  • Applied Physics Letters, Vol. 104, Issue 25
  • DOI: 10.1063/1.4885354

Structural and magnetic properties of ultrathin epitaxial Fe films on GaAs(001) and related semiconductor substrates
journal, March 2005


Perpendicular magnetic anisotropy in the Heusler alloy Co 2 TiSi/GaAs(001) hybrid structure
journal, May 2015

  • Dau, M. T.; Jenichen, B.; Herfort, J.
  • AIP Advances, Vol. 5, Issue 5
  • DOI: 10.1063/1.4921237

Structural and electronic properties of molecular beam epitaxially grown Ni1+xTiSn films
journal, June 2017


Superconductivity in palladium-based Heusler compounds
journal, February 2009


Investigations of the electronic and magnetic structures at Heusler alloy surface: Co 2 TiGe (0 0 1)
journal, August 2015

  • Hussain, Moaid K.; Gao, G. Y.; Yao, Kai-Lun
  • Journal of Electron Spectroscopy and Related Phenomena, Vol. 203
  • DOI: 10.1016/j.elspec.2015.05.015

Surface and electronic structure of epitaxial PtLuSb (001) thin films
journal, May 2014

  • Patel, Sahil J.; Kawasaki, Jason K.; Logan, John
  • Applied Physics Letters, Vol. 104, Issue 20
  • DOI: 10.1063/1.4879475

Interfacial reactions in the Ti/GaAs system
journal, May 1988

  • Kim, Ki Bum; Kniffin, Margaret; Sinclair, Robert
  • Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 6, Issue 3
  • DOI: 10.1116/1.575728

Arsenic passivation of MBE grown GaAs(100): structural and electronic properties of the decapped surfaces
journal, May 1992


Anomalous transport properties of the half-metallic ferromagnets Co 2 TiSi, Co 2 TiGe and Co 2 TiSn
journal, September 2011

  • Barth, Joachim; Fecher, Gerhard H.; Balke, Benjamin
  • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 369, Issue 1951
  • DOI: 10.1098/rsta.2011.0183

Time-Reversal-Breaking Weyl Fermions in Magnetic Heusler Alloys
journal, November 2016


Simple rules for the understanding of Heusler compounds
journal, May 2011


Discovery of a Weyl fermion semimetal and topological Fermi arcs
journal, July 2015


Friedel oscillations due to Fermi arcs in Weyl semimetals
journal, November 2012


Epitaxy, overlayer growth, and surface segregation for Co/GaAs(110) and Co/GaAs(100)- c (82)
journal, February 1987


Quantum oscillations from surface Fermi arcs in Weyl and Dirac semimetals
journal, October 2014

  • Potter, Andrew C.; Kimchi, Itamar; Vishwanath, Ashvin
  • Nature Communications, Vol. 5, Issue 1
  • DOI: 10.1038/ncomms6161

Magnetic and half-metallic properties of the full-Heusler alloys Co2TiX(X=Al,Ga;Si,Ge,Sn;Sb)
journal, May 2005

  • Lee, S. C.; Lee, T. D.; Blaha, P.
  • Journal of Applied Physics, Vol. 97, Issue 10
  • DOI: 10.1063/1.1853899

Epitaxial growth of ferromagnetic Ni2MnGa on GaAs(001) using NiGa interlayers
journal, December 2000

  • Dong, J. W.; Chen, L. C.; Xie, J. Q.
  • Journal of Applied Physics, Vol. 88, Issue 12
  • DOI: 10.1063/1.1326461

Effect of substrate roughness on microstructure, uniaxial anisotropy, and coercivity of Co/Pt multilayer thin films
journal, May 1994

  • Chang, Chung‐Hee; Kryder, Mark H.
  • Journal of Applied Physics, Vol. 75, Issue 10
  • DOI: 10.1063/1.356810

Slater-Pauling behavior and origin of the half-metallicity of the full-Heusler alloys
journal, November 2002


Half-metallic ferromagnets: From band structure to many-body effects
journal, April 2008


Molecular beam epitaxy growth of ferromagnetic single crystal (001) Ni2MnGa on (001) GaAs
journal, September 1999

  • Dong, J. W.; Chen, L. C.; Palmstro/m, C. J.
  • Applied Physics Letters, Vol. 75, Issue 10
  • DOI: 10.1063/1.125009

Properties of Fe single‐crystal films grown on (100)GaAs by molecular‐beam epitaxy
journal, April 1987

  • Krebs, J. J.; Jonker, B. T.; Prinz, G. A.
  • Journal of Applied Physics, Vol. 61, Issue 7
  • DOI: 10.1063/1.337886

Room-temperature magnetic topological Weyl fermion and nodal line semimetal states in half-metallic Heusler Co2TiX (X=Si, Ge, or Sn)
journal, December 2016

  • Chang, Guoqing; Xu, Su-Yang; Zheng, Hao
  • Scientific Reports, Vol. 6, Issue 1
  • DOI: 10.1038/srep38839

Spin polarization studies in half-metallic Co 2 TiX (X = Ge and Sn) Heusler alloys
journal, January 2016


Structure and interface composition of Co layers grown on As-rich GaAs(001) c(4×4) surfaces
journal, January 2002

  • Lüdge, K.; Schultz, B. D.; Vogt, P.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 20, Issue 4
  • DOI: 10.1116/1.1491993

ErAs interlayers for limiting interfacial reactions in Fe/GaAs(100) heterostructures
journal, January 2002

  • Schultz, B. D.; Farrell, H. H.; Evans, M. M. R.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 20, Issue 4
  • DOI: 10.1116/1.1491994

Observation of a topologically non-trivial surface state in half-Heusler PtLuSb (001) thin films
journal, June 2016

  • Logan, J. A.; Patel, S. J.; Harrington, S. D.
  • Nature Communications, Vol. 7, Issue 1
  • DOI: 10.1038/ncomms11993

Molecular beam epitaxy growth and properties of Co 2 TiSi thin films on GaAs(0 0 1): the effect of growth temperature
journal, December 2014


Surface reconstructions and transport of epitaxial PtLuSb (001) thin films grown by MBE
journal, February 2016


Covalent bonding and the nature of band gaps in some half-Heusler compounds
journal, February 2006

  • Kandpal, Hem Chandra; Felser, Claudia; Seshadri, Ram
  • Journal of Physics D: Applied Physics, Vol. 39, Issue 5
  • DOI: 10.1088/0022-3727/39/5/S02

Anomalous transport of Weyl fermions in Weyl semimetals
journal, February 2014


Relativistic Hartree–Fock X-ray and electron scattering factors
journal, May 1968