About the Cu-related green luminescence band in ZnO

Reshchikov, M. A.; Avrutin, V.; Izyumskaya, N.; Shimada, Ryoko; Morkoç, H.; Novak, Steven W.

doi:10.1116/1.3110023

Cited by 30 publications

(30 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The emission by excitons was concluded to be the origin of UV emission in ZnO thin films. However, the exact origin of green emission is still in dispute, although defects such as oxygen vacancies [12], oxygen interstitials, zinc vacancies [13][14][15], zinc interstitials [16], copper [17,18] and oxide antisites [19] are suggested to be responsible for the green PL by many researchers.…”

Section: Introductionmentioning

confidence: 98%

Green photoluminescence in ZnO crystals: a combined study using positron annihilation, photoluminescence, and hall measurements

Parmar

Swain

Lynn

2015

J Mater Sci: Mater Electron

View full text Add to dashboard Cite

The 510-525 nm green emission in melt grown Cermet bulk ZnO single crystals is investigated. It was observed that the green emission intensity is strongly influenced by the presence of zinc vacancies. Green emission intensity was found to decrease by more than two orders of magnitude by reducing zinc vacancy concentration upon annealing in cadmium metal environment. Positron annihilation spectroscopy, photoluminescence and hall measurements support this argument.

show abstract

Section: Introductionmentioning

confidence: 98%

Green photoluminescence in ZnO crystals: a combined study using positron annihilation, photoluminescence, and hall measurements

Parmar

Swain

Lynn

2015

J Mater Sci: Mater Electron

View full text Add to dashboard Cite

show abstract

“…One is that substitutional Cu 2þ (Cu s 2þ ) species on Zn sites can immediately capture these excitons, forming an acceptor-type exciton bound to the neutral d 9 configuration, which can be described as [Cu s þ , h]. 19 The other case is that dissociated excitons will distribute electrons or holes to those uncompensated charge traps, e.g., Cu s þ or highly ionized donor atoms (see Fig. 1(a)).…”

mentioning

confidence: 99%

Optical demagnetization in defect-mediated ferromagnetic ZnO:Cu films

Zhu

et al. 2014

Applied Physics Letters

View full text Add to dashboard Cite

Optical demagnetization effect has been observed in a defect-rich ZnO:Cu film. Phenomenally, UV illumination can effectively quench dual-donor oxygen vacancy (VO) and interstitial zinc (Zni) mediated magnetic ordering (90% loss) with carrier recapture in ionized Zni (Zni2+ rather than Zni+) traps. The involvement of carriers by means of metal Zn vapor annealing provides a bound carrier related magnetic scenario, stressing a more significant place of bound carrier rather than free carrier. Using light correlated electron spin resonance and magnetic measurements, the magnetic “on” and “off” state can be continuously manipulated via UV light, which is explained by the reversible process of [Cus+/Cus2+] + Zni2+ ↔ [Cus+, h] + Zni+ (s and h denote the substitutional Cu ions on Zn sites in ZnO lattice and hole carrier, respectively). A slow charge-transfer process (∼15 μs) from Zni+ bound carriers to [Cus+, h] states determines the unexpected optical demagnetization, well corresponding to control experiments.

show abstract

“…[1][2][3][4][5][6][7][8][9][10][11] These ions are often present at low concentrations (< 5 Â 10 16 cm À3 ) as a residual impurity in ZnO bulk crystals, thin films, and nanoparticles. Much higher concentrations can be achieved by doping during growth or by post-growth diffusion.…”

Section: Introductionmentioning

confidence: 99%

“…Copper in ZnO can be present as Cu þ (3d 10 ) or Cu 2þ (3d 9 ) ions substituting for Zn 2þ ions. As is customary, ionic notation is used to describe the different charge states of copper ions.…”

Section: Introductionmentioning

confidence: 99%

“…Electron paramagnetic resonance (EPR) and near-infrared (NIR) absorption techniques are two direct high-resolution spectroscopy methods to monitor Cu 2þ ions in ZnO crystals (i.e., the incomplete d shell of these ions gives rise to unique spectroscopic signatures). [1][2][3][4][7][8][9][10][11] The Cu 2þ EPR spectrum, with g jj ¼ 0.729 and g ? ¼ 1.520, shows well-resolved hyperfine lines from 63 Cu and 65 Cu nuclei.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Copper doping of ZnO crystals by transmutation of 64Zn to 65Cu: An electron paramagnetic resonance and gamma spectroscopy study

Recker

McClory

Holston

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

Transmutation of 64Zn to 65Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the 65Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of 64Zn nuclei to 65Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu2+ ions (where 63Cu and 65Cu hyperfine lines are easily resolved). A spectrum from isolated Cu2+ (3d9) ions acquired after the neutron irradiation showed only hyperfine lines from 65Cu nuclei. The absence of 63Cu lines in this Cu2+ spectrum left no doubt that the observed 65Cu signals were due to transmuted 65Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu+-H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu+-H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900 °C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

show abstract

About the Cu-related green luminescence band in ZnO

Abstract: Articles you may be interested inThe high temperature photoluminescence and optical absorption of undoped ZnO single crystals and thin films

Cited by 30 publications

References 22 publications

Green photoluminescence in ZnO crystals: a combined study using positron annihilation, photoluminescence, and hall measurements

Green photoluminescence in ZnO crystals: a combined study using positron annihilation, photoluminescence, and hall measurements

Optical demagnetization in defect-mediated ferromagnetic ZnO:Cu films

Copper doping of ZnO crystals by transmutation of 64Zn to 65Cu: An electron paramagnetic resonance and gamma spectroscopy study

Contact Info

Product

Resources

About