Violet Luminescence from Ge+-Implanted SiO2 Film on Si Substrate

1996 ◽  
Vol 438 ◽  
Author(s):  
Xi-Mao Bao ◽  
Ting Gao ◽  
Feng Yan ◽  
Song Tong
Keyword(s):  
Low Temperature ◽  
Thermal Annealing ◽  
Quantum Confinement ◽  
Quantum Confinement Effect ◽  
Sio2 Film ◽  
Confinement Effect ◽  
Si Substrate ◽  
Ultraviolet Excitation ◽  
Violet Luminescence ◽  
Thermally Grown

AbstractThe SiO2 films thermally grown on crystalline Si were implanted with Ge ions at 60 keV with doses of l×1015 cm-2 and l×1016 cm-2, followed by thermal annealing at various temperatures. Under an ultraviolet excitation of 240 nm, the films exhibit intense violet luminescence with a peak at 396 nm. This peak is ascribed to the T1 → S0 transition in GeO formed during implantation and annealing. After 1100°C annealing, Ge clusters were formed in an SiO2 matrix and a PL peak at 840 nm, due to the quantum confinement effect, which was measured at low temperature (77 K).

Comparative Analysis of ZnS:Mn2+ Nanophosphors Prepared by Hydrothermal and Low Temperature Precipitation Methods

2007 ◽  
Vol 128 ◽  
pp. 53-58 ◽  
Author(s):  
Je Hong Park ◽  
Sung Hoon Lee ◽  
Jong Su Kim ◽  
Tae Wan Kim ◽  
Hong Lee Park
Keyword(s):  
Low Temperature ◽  
Quantum Confinement ◽  
Transition Probability ◽  
Quantum Confinement Effect ◽  
Confinement Effect ◽  
Precipitation Method ◽  
Cubic Phase ◽  
Decay Times ◽  
Hydrothermal Precipitation ◽  
20 Nm

Manganese-doped ZnS nanophosphors were synthesized by two different methods: hydrothermal and low-temperature precipitation methods. The nanophosphors prepared by the hydrothermal precipitation and low-temperature methods had the size of 20 nm and 4 nm, respectively, and both were the cubic phase. The emission intensity of the nanophosphor prepared by the hydrothermal method was optimized at 10 mole % of Mn2+ concentration whereas that by low-temperature precipitation method was optimized at 3 mole % of Mn2+. The precipitationprepared nanophosphor, of size 4nm, showed a blueshift in the excitation spectrum and a redshift in the emission spectrum compared to the hydrothermal-prepared 20 nm nanophosphor. These phenomena can be explained in terms of the quantum confinement effect. The decay times especially were lengthened with decreasing particle size. This can be explained in terms of the variation in the transition probability induced from the quantum confinement effect.

Tunable Quantum Confinement Effect on Non-volatile Thin Film Polymer Memory Device

2008 ◽  
Author(s):  
Augustin J. Hong ◽  
Kang L. Wang ◽  
Wei Lek Kwan ◽  
Yang Yang ◽  
Dayanara Parra ◽  
...  
Keyword(s):  
Thin Film ◽  
Quantum Confinement ◽  
Quantum Confinement Effect ◽  
Memory Device ◽  
Confinement Effect ◽  
Film Polymer ◽  
Polymer Memory

Quantum confinement effect in nanocomposites

2001 ◽  
Vol 182 (3-4) ◽  
pp. 251-257 ◽  
Author(s):  
D. Chakravorty ◽  
S. Banerjee ◽  
T.K. Kundu
Keyword(s):  
Quantum Confinement ◽  
Quantum Confinement Effect ◽  
Confinement Effect

Size-dependent penetration of carbon dots inside the ferritin nanocages: evidence for the quantum confinement effect in carbon dots

2015 ◽  
Vol 17 (19) ◽  
pp. 12833-12840 ◽  
Author(s):  
Arpan Bhattacharya ◽  
Surajit Chatterjee ◽  
Roopali Prajapati ◽  
Tushar Kanti Mukherjee
Keyword(s):  
Carbon Dots ◽  
Quantum Confinement ◽  
Quantum Confinement Effect ◽  
Confinement Effect ◽  
Size Dependent ◽  
Pl Quenching

Size-dependent penetration of CDs through the ferritin channels has been successfully demonstrated by means of λex-dependent PL quenching of CDs by the Fe3+ ions of ferritin.

SIZE-DEPENDENT NONRESONANT THIRD-ORDER NONLINEAR SUSCEPTIBILITIES OF CdS CLUSTERS FROM 7 TO 120 Å

1992 ◽  
Vol 01 (04) ◽  
pp. 683-698 ◽  
Author(s):  
YING WANG ◽  
NORMAN HERRON
Keyword(s):  
Refractive Index ◽  
Quantum Confinement ◽  
Optical Switching ◽  
Quantum Confinement Effect ◽  
Surrounding Medium ◽  
Confinement Effect ◽  
Third Order ◽  
Size Dependent ◽  
Size Regime ◽  
Fundamental Wavelength

We report the third-order nonlinear susceptibilities χ(3) of CdS clusters (quantum dots) from 7 to 120 Å, measured by third-harmonic generation technique at a fundamental wavelength of 1.91 µm. In the size regime studied, the value of χ(3) first increases with cluster size and then levels off for cluster diameter larger than 60 Å. The volume normalized χ(3) of CdS cluster is about a factor of 2 higher than that of the bulk. These data can be explained by the enhancement in electric field inside the clusters due to the dielectric confinement effect. The size and wavelength dependences of this local field effect have been calculated for CdS clusters. Several trends in the nonresonant χ(3) can be identified: (i) In the absence of quantum confinement effect, the magnitude of χ(3) should be constant in the < 200 Å size regime. It then increases with increasing particle size until the structural resonance regime is reached. (ii) The magnitude of χ(3) can be enhanced by either lowering the refractive index of the surrounding medium or raising the refractive index of the semiconductors. (iii) Quantum confinement, which shifts the band gap to the blue and lowers the refractive index of the semiconductor clusters, reduces the nonresonant χ(3). This is in direct contrast to the resonant nonlinearity which is enhanced by the quantum-confinement effect. Finally, we discuss the size-dependent figure-of-merit of CdS composites for all-optical switching.

Graphene/Si-Quantum-Dot Heterojunction Diodes Showing High Photosensitivity Compatible with Quantum Confinement Effect

2015 ◽  
Vol 27 (16) ◽  
pp. 2614-2620 ◽  
Author(s):  
Dong Hee Shin ◽  
Sung Kim ◽  
Jong Min Kim ◽  
Chan Wook Jang ◽  
Ju Hwan Kim ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Quantum Confinement ◽  
Quantum Confinement Effect ◽  
Confinement Effect ◽  
Si Quantum Dot ◽  
Heterojunction Diodes ◽  
High Photosensitivity
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