Electron paramagnetic resonance ofZn1−xMnxOthin films and single crystals

Transition‐Metal Doped Zinc Oxide Nanowires

“…and g k , respectively. [26] The reciprocal EPR intensity versus temperature for the sample of 2.15 % Co is plotted in Figure 5 b. The Curie Law predicts that this would be a straight line for isolated, paramagnetic Co 2+ ions; [27] however, we observe a deviation from Curie behavior in the temperature region 25-30 K. The behavior is found in other nanowire samples with different cobalt concentrations as well.…”

Room-temperature ferromagnetic Mn-alloyed ZnO films obtained by pulsed laser deposition

“…4. The expected 2þ valence of the Mn ions substituting for Zn 2þ ions has been confirmed by electron paramagnetic resonance (EPR) measurements using the X-band EPR spectroscopy with a constant microwave frequency of 9.5 GHz [31]. For an insulating Mn-alloyed ZnO film on c-plane sapphire with 1.7 at% Mn (Fig.…”

“…5 involves the broadening of the Mn 2þ spectrum (line A) by dipolar interactions (line B) and the addition of a broad single Lorentzian line (line C). Based on the modeled negative fine-structure splitting constant, we estimate that the trigonal distortion of the Mn-O 4 tetrahedron in Mn-alloyed ZnO thin films and single crystals is the same at a Mn content of about 4.5 at% [31]. Sati et al [32] determined a positive fine-structure splitting constant in Co-alloyed ZnO and used the modeled EPR parameters to reveal a magnetic anisotropy with the c-axis being the hard axis of magnetization.…”

Role of defects in ferromagnetism inZn1−xCoxO: A hybrid density-functional study

“…Recent magnetic resonance, [27][28][29][30][31][32] carrier mobility, 33 positron annihilation spectroscopy, 34 and first-principles calculations [35][36][37] have given a fuller picture of defect-induced electronic states in ZnO. Magnetic resonance techniques 8,9,38 have been applied to Zn 1−x Co x O and Zn 1−x Mn x O films and nanoclusters. As noted above, these studies 8,9,38,39 as well as x-ray magnetic circular dichroism, 12,39 which probe the local crystal structure about the transition-metal ion, have concluded that the transition-metal ions substitute for a Zn ion.…”

“…Magnetic resonance techniques 8,9,38 have been applied to Zn 1−x Co x O and Zn 1−x Mn x O films and nanoclusters. As noted above, these studies 8,9,38,39 as well as x-ray magnetic circular dichroism, 12,39 which probe the local crystal structure about the transition-metal ion, have concluded that the transition-metal ions substitute for a Zn ion. Epitaxial growth of thin films with ͑110͒ orientation has been achieved, 12 and there is considerable anisotropy of the magnetism in the thin film.…”