Anomalous excitation-power dependence of band-edge emission in Si involving radiation-induced defects

2020 ◽  
Vol 59 (10) ◽  
pp. 106502 ◽  
Author(s):  
Shota Asahara ◽  
Michio Tajima ◽  
Yuta Satake ◽  
Atsushi Ogura
Keyword(s):  
Excitation Power ◽  
Band Edge ◽  
Band Edge Emission ◽  
Power Dependence ◽  
Edge Emission ◽  
Radiation Induced ◽  
Induced Defects

The compositional and optical characterizations of InGaAsN alloy semiconductor grown by MOVPE

2002 ◽  
Vol 744 ◽  
Author(s):  
Sakuntam Sanorpim ◽  
Fumihiro Nakajima ◽  
Ryuji Katayama ◽  
Kentaro Onabe ◽  
Yashihiro Shiraki
Keyword(s):  
Room Temperature ◽  
Excitation Power ◽  
Band Edge ◽  
Near Band Edge Emission ◽  
Near Band Edge ◽  
Band Edge Emission ◽  
Optical Investigation ◽  
Edge Emission ◽  
Alloy Films ◽  
Pl Spectra

ABSTRACTWe report on the compositional and optical investigation of InGaAs(N) alloy films grown on GaAs (001) substrates by low-pressure (60 Torr) metalorganic vapor phase epitaxy (MOVPE). The alloy films with the room-temperature photoreflactance (PR) signal (Eo transition) wavelength range of 0.98–1.36 m have been grown. The variation in PL characteristics of the InGaAs(N) alloy films has been investigated as a function of alloy composition, excitation power and temperature. At low temperatures (T<100K), the PL spectra with several sub-peaks include localization emission as well as near-band-edge emission. On the other hand, the room-temperature PL properties for InxGa1-xAs1-yNy (x = 10.5% and 17.0% and y < 2%) are excellent with a single near-band-edge emission peak corresponding to their own Eo transition. The evolution of PL spectra with excitation power and temperature led to an insight into the nature of the near-band-edge states. The temperature dependence of integrated PL intensity indicates the presence of a large density of non-radiative recombination centers, showing a behavior characterized by two activation energies. Our results suggest that the origin of localization in InGaAsN alloy films is the alloy inhomogeneities of both In and N, which may results in the characteristic carrier dynamics.

Photoluminescence Study of Hydrogen-Related Defects in Silicon

1993 ◽  
Vol 324 ◽  
Author(s):  
A. Henry ◽  
B. Monemar ◽  
J.L. LindstrÖm ◽  
Y. Zhang ◽  
J.W. Corbett
Keyword(s):  
Low Temperature ◽  
Band Gap ◽  
Hydrogen Plasma ◽  
Broad Band ◽  
Excitation Power ◽  
Power Dependence ◽  
Radiation Induced ◽  
Hydrogen Exposure ◽  
Induced Defects ◽  
Very Low Temperature

AbstractThe effect of ion-implantation followed by a rapid thermal annealing was investigated in borondoped silicon using photoluminescence (PL) spectroscopy. The radiation induced defects giving rise to the G, W and C PL lines are completely passivated by a hydrogen plasma treatment. However this hydrogen exposure also introduces broad and deep luminescence structure as well as new sharp PL lines very near the silicon band gap. Up to twelve new lines are observed at low temperature (< 20K). One of them exhibits a very low exciton localisation energy (≈ 2 meV) compared to the value measured for classical shallow donors or acceptors, and is observed only at very low temperature (≈4K). A broad deep PL band with a halfwidth of 30 meV is observed at around 925 meV. The excitation power dependence and the temperature dependence of the PL intensity of these sharp lines and the broad band are presented. Tentative correlations with the data currently available in the literature are presented for the understanding of the formation of the defects associated to the broad band as well as the sharp near band gap PL lines.

scholarly journals Core Nanoparticle Engineering for Narrower and More Intense Band-Edge Emission from AgInS2/GaSx Core/Shell Quantum Dots

Nanomaterials ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1763 ◽  
Author(s):  
Watcharaporn Hoisang ◽  
Taro Uematsu ◽  
Takahisa Yamamoto ◽  
Tsukasa Torimoto ◽  
Susumu Kuwabata
Keyword(s):  
Surface Passivation ◽  
Precursor Solution ◽  
Silver Sulfide ◽  
Band Edge ◽  
Crystal Phase ◽  
Band Edge Emission ◽  
Edge Emission ◽  
Orthorhombic Crystal ◽  
Metal Precursor ◽  
Ag2s Nanoparticles

Highly luminescent silver indium sulfide (AgInS2) nanoparticles were synthesized by dropwise injection of a sulfur precursor solution into a cationic metal precursor solution. The two-step reaction including the formation of silver sulfide (Ag2S) nanoparticles as an intermediate and their conversion to AgInS2 nanoparticles, occurred during the dropwise injection. The crystal structure of the AgInS2 nanoparticles differed according to the temperature of the metal precursor solution. Specifically, the tetragonal crystal phase was obtained at 140 °C, and the orthorhombic crystal phase was obtained at 180 °C. Furthermore, when the AgInS2 nanoparticles were coated with a gallium sulfide (GaSx) shell, the nanoparticles with both crystal phases emitted a spectrally narrow luminescence, which originated from the band-edge transition of AgInS2. Tetragonal AgInS2 exhibited narrower band-edge emission (full width at half maximum, FWHM = 32.2 nm) and higher photoluminescence (PL) quantum yield (QY) (49.2%) than those of the orthorhombic AgInS2 nanoparticles (FWHM = 37.8 nm, QY = 33.3%). Additional surface passivation by alkylphosphine resulted in higher PL QY (72.3%) with a narrow spectral shape.

Stable enhancement of near-band-edge emission of ZnO nanowires by hydrogen incorporation

2010 ◽  
Vol 21 (6) ◽  
pp. 065709 ◽  
Author(s):  
A Dev ◽  
R Niepelt ◽  
J P Richters ◽  
C Ronning ◽  
T Voss
Keyword(s):  
Zno Nanowires ◽  
Band Edge ◽  
Near Band Edge Emission ◽  
Near Band Edge ◽  
Band Edge Emission ◽  
Edge Emission ◽  
Hydrogen Incorporation

Using dispersion theory to interpret the polarization properties of the band-edge emission in GaN crystals

1987 ◽  
Vol 61 (6) ◽  
pp. 381-384
Author(s):  
Bao Qingcheng ◽  
Zhang Fengling ◽  
Li Duolu ◽  
Dai Rensong ◽  
Xu Xurong
Keyword(s):  
Band Edge ◽  
Band Edge Emission ◽  
Dispersion Theory ◽  
Edge Emission

Enhancement of Photoluminescence from Organic and Inorganic Surface Passivated ZnS Quantum Dots

2001 ◽  
Vol 667 ◽  
Author(s):  
Hatim Mohamed El-Khair ◽  
Ling Xu ◽  
Mingha Li ◽  
Yi Ma ◽  
Xinfan Huang ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Organic Coating ◽  
Band Edge ◽  
Band Edge Emission ◽  
Trap States ◽  
Edge Enhancement ◽  
Edge Emission ◽  
Inorganic And Organic

ABSTRACTZnS quantum dots (QDs) chemically synthesized in PVP stabilizing medium have been coated with Zn(OH)2, SiO2and polystyrene (PS) shells as inorganic and organic passivation agents. to synthesize ZnS/Zn(OH)2, ZnS/SiO2and ZnS/PS QDs. PL properties of inorganically passivated ZnS/Zn(OH)2 and ZnS/SiO2 had reported band edge enhancement of 8-10 times, while organically passivated ZnS/PS QDs exhibit tremendous enhancement of band edge emission as much as 10-15 times,. Therefore inorganic and organic coating can passivate trap states of different energies on the surface of ZnS QDs.

Enhancement of the near-band-edge emission of CuI by Cl doping

2019 ◽  
Vol 205 ◽  
pp. 337-341 ◽  
Author(s):  
Fengrui Li ◽  
Mu Gu ◽  
Xiaolin Liu ◽  
Shuangqiang Yue ◽  
Jiajie Zhu ◽  
...  
Keyword(s):  
Band Edge ◽  
Near Band Edge Emission ◽  
Near Band Edge ◽  
Band Edge Emission ◽  
Edge Emission
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