Evidence of intrinsic ferromagnetism in individual dilute magnetic semiconducting nanostructures
Source abstract
Abstract
Semiconductors doped with magnetic ions, also known as dilute magnetic semiconductors, are both semiconducting and ferromagnetic. It remains unclear, however, whether this ferromagnetism is intrinsic, as is required for spintronic applications, or is due instead to dopant clustering. Here, we report conclusive evidence for intrinsic ferromagnetism in individual ZnO nanoparticles doped with transition metal ions. Through a simultaneous magnetic and microstructural characterization using electron magnetic chiral dichroism and channelling-enhanced electron energy loss microanalysis, respectively, we show that ZnO nanoparticles have intrinsic ferromagnetism when doped with cobalt, but not when doped with iron.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: ZnO doping and properties · Copper-based nanomaterials and applications · Advanced Condensed Matter Physics
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References (23)
Show source-provided references
1. Wolf, S. A. et al. Spintronics: a spin-based electronics vision for the future. Science 294, 1488–1495 (2001).10.1126/science.1065389 ↗
2. Sharma, P. et al. Ferromagnetism above room temperature in bulk and transparent thin films of Mn-doped ZnO. Nature Mater. 2, 673–677 (2003).10.1038/nmat984 ↗
3. Kittilstved, K. R., Lin, W. K. & Gamelin, D. R. Electronic structure origins of polarity-dependent high-TC ferromagnetism in oxide-diluted magnetic semiconductors. Nature Mater. 5, 291–297 (2006).10.1038/nmat1616 ↗
4. Radovanovic, P. V. & Gamelin, D. R. High-temperature ferromagnetism in Ni2+-doped aggregates prepared from colloidal diluted magnetic semiconductor quantum dots. Phys. Rev. Lett. 91, 157202 (2003).10.1103/PhysRevLett.91.157202 ↗
5. Quilty, J. W. et al. Signature of carrier-induced ferromagnetism in Ti1–xCoxO2–δ: exchange interaction between high-spin Co2+ and the Ti 3d conduction band. Phys. Rev. Lett. 96, 027202 (2006).10.1103/PhysRevLett.96.027202 ↗
6. Neal, J. R. et al. Room-temperature magneto-optics of ferromagnetic transition-metal- doped ZnO thin films. Phys. Rev. Lett. 96, 197208 (2006).10.1103/PhysRevLett.96.197208 ↗
7. Matsukura, F., Ohno, H., Shen, A. & Sugawara, Y. Transport properties and origin of ferromagnetism in (Ga,Mn)As. Phys. Rev. B. 57, R2037–R2040 (1997).10.1103/PhysRevB.57.R2037 ↗
8. Toyosaki, H. et al. Anomalous Hall effect governed by electron doping in a room-temperature transparent ferromagnetic semiconductor. Nature Mater. 3, 221–224 (2004).10.1038/nmat1099 ↗
9. Shinde, S. R. et al. Co-occurrence of superparamagnetism and anomalous Hall effect in highly reduced cobalt-doped rutile TiO2–δ films. Phys. Rev. Lett. 92, 166601 (2004).10.1103/PhysRevLett.92.166601 ↗
10. Xu, Q. Y. et al. Room-temperature ferromagnetism in ZnO films due to defects. Appl. Phys. Lett. 92, 082508 (2008).10.1063/1.2885730 ↗
11. Coey, J. M. D., Venkatesan, M. & Fitzgerald, C. B. Donor impurity band exchange in dilute ferromagnetic oxides. Nature Mater. 4, 173–179 (2005).10.1038/nmat1310 ↗
12. Venkatesan, M., Fitzgerald, C. B., Lunney, J. G. & Coey, J. M. D. Anisotropic ferromagnetism in substituted zinc oxide. Phys. Rev. Lett. 93, 177206 (2004).10.1103/PhysRevLett.93.177206 ↗
13. Jiang, N. et al. Polarity determination by atomic location by channeling-enhanced microanalysis. Appl. Phys. Lett. 80, 389–391 (2001).10.1063/1.1433919 ↗
14. Kong, X., Hu, G. Q., Duan, X. F., Lu, Y. & Liu, X. L. Polarity determination for GaN thin films by electron energy-loss spectroscopy. Appl. Phys. Lett. 81, 1990–1992 (2002).10.1063/1.1504876 ↗
15. Liu, Y. Z. et al. Co location and valence state determination in ferromagnetic ZnO:Co thin films by atom-location-by-channeling-enhanced-microanalysis electron energy-loss spectroscopy. Appl. Phys. Lett. 90, 154101 (2007).10.1063/1.2720713 ↗
16. Wang, X. F. et al. Signature of intrinsic high-temperature ferromagnetism in cobalt-doped zinc oxide nanocrystals. Adv. Mater. 18, 2476–2480 (2006).10.1002/adma.200600396 ↗
17. Hébert, C. & Schattschneider, P. A proposal for dichroic experiments in the electron microscope. Ultramicroscopy 96, 463–468 (2003).10.1016/S0304-3991(03)00108-6 ↗
18. Schattschneider, P. et al. Detection of magnetic circular dichroism using a transmission electron microscope. Nature 441, 486–488 (2006).10.1038/nature04778 ↗
19. Stöhr, J. Exploring the microscopic origin of magnetic anisotropies with X-ray magnetic circular dichroism (XMCD) spectroscopy. J. Magn. Magn. Mater. 200, 470–497 (1999).10.1016/S0304-8853(99)00407-2 ↗
20. Egerton, R. F. Electron Energy Loss Spectroscopy in the Electron Microscope 2nd edn (Plenum Press, 1996).10.1007/978-1-4757-5099-7 ↗
21. Kittel, C. Introduction to Solid States Physics 7th edn (Wiley, 1996).
22. Muller, S., Zhou, M. J., Li, Q. & Ronning, C. Intra-shell luminescence of transition-metal-implanted zinc oxide nanowires. Nanotechnology 20, 135704 (2009).10.1088/0957-4484/20/13/135704 ↗
23. Schattschneider, P. et al. Magnetic circular dichroism in EELS: Towards 10 nm resolution. Ultramicroscopy 108, 433–438 (2008).10.1016/j.ultramic.2007.07.002 ↗