DEVELOPING A NEW DEFECT CLUSTER INDEX

Abstract The γ-phase Cuprous Iodide (CuI) emerges as a promising transparent p-type semiconductor for next-generation display technology because of its wide direct band gap, intrinsic p-type conductivity, and high carrier mobility. Two main peaks are observed in its photoluminescence (PL). One is short wavelength (410-430 nm) emission, which is well attributed to the electronic transitions at Cu vacancy, whereas the other long wavelength emission (680-720 nm) has not been fully understood. In this paper, through first-principles simulations, we investigate the formation energies and emission line shape for various defects, and discover that the intrinsic point defect cluster V_I+Cu_i^(2+) is the source of the long wavelength emission. Our finding is further supported by the prediction that the defect concentration decreases dramatically as the chemical condition changes from Cu-rich to I-rich, explaining the significant reduction in the red light emission if CuI is annealed in abundant I environment.

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Effect of injected hydrogen on defect cluster formation in electron irradiated austenitic stainless steel

Journal of Nuclear Materials ◽

10.1016/0022-3115(85)90189-8 ◽

1985 ◽

Vol 133-134 ◽

pp. 459-462 ◽

Cited By ~ 14

Author(s):

S. Ohnuki ◽

H. Takahashi ◽

T. Takeyama ◽

F. Wan

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Cluster Formation ◽

Defect Cluster

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Damage rate dependence of defect cluster nucleation in tungsten during irradiation

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2013.04.014 ◽

2013 ◽

Vol 442 (1-3) ◽

pp. S773-S775 ◽

Cited By ~ 5

Author(s):

Y. Yamamoto ◽

J. Yoshimatsu ◽

K. Morishita

Keyword(s):

Defect Cluster ◽

Rate Dependence ◽

Damage Rate

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Ferromagnetism in lightly Gd doped GaN: The role of defects

MRS Proceedings ◽

10.1557/opl.2011.177 ◽

2011 ◽

Vol 1290 ◽

Cited By ~ 2

Author(s):

J. K. Mishra ◽

S. Dhar ◽

M. A. Khaderabad ◽

O. Brandt

Keyword(s):

Magnetic Properties ◽

Molecular Beam Epitaxy ◽

Saturation Magnetization ◽

Magnetic Moment ◽

Molecular Beam ◽

Defect Density ◽

Defect Cluster ◽

Clear Correlation ◽

Defect Band

ABSTRACTGd:GaN layers grown with different Gd concentrations by molecular beam epitaxy (MBE) are studied using photoconductivity and photo-thermoelectric power spectroscopy. Our study reveals that the incorporation of Gd produces a large concentration of acceptor-like defects in the GaN lattice. The defect band is found to be located ~450meV above the valence band. Moreover, the concentration of defects is found to increase with the Gd concentration. The effect of annealing on the structural and the magnetic properties of GaN implanted with Gd is also investigated. A clear correlation between the saturation magnetization and the defect density is observed in implanted samples. The colossal magnetic moment per Gd ion and the ferromagnetism observed in this material is explained in terms of the formation of giant defect cluster around each Gd ion.

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