Room temperature photoluminescence intensity enhancement in GaAs1-xBix alloys

2011 ◽  
Vol 9 (2) ◽  
pp. 259-261 ◽  
Author(s):  
A. R. Mohmad ◽  
F. Bastiman ◽  
J. S. Ng ◽  
S. J. Sweeney ◽  
J. P. R. David
Keyword(s):  
Room Temperature ◽  
Photoluminescence Intensity ◽  
Room Temperature Photoluminescence ◽  
Intensity Enhancement

Strong room temperature 510 nm emission from cubic InGaN/GaN multiple quantum wells

2004 ◽  
Vol 831 ◽  
Author(s):  
S.F. Li ◽  
D.J. As ◽  
K. Lischka ◽  
D.G. Pacheco-Salazar ◽  
L.M.R. Scolfaro ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Room Temperature ◽  
Molecular Beam ◽  
Bandgap Energy ◽  
Multiple Quantum ◽  
Photoluminescence Intensity ◽  
Excitation Spectra ◽  
Room Temperature Photoluminescence ◽  
Double Heterostructures ◽  
Peak Energy

ABSTRACTCubic InGaN/GaN double heterostructures and multi-quantum-wells have been grown by Molecular Beam Epitaxy on cubic 3C-SiC. We find that the room temperature photoluminescence spectra of our samples has two emission peaks at 2.4 eV and 2.6 e V, respectively. The intensity of the 2.6 eV decreases and that of the 2.4 eV peak increases when the In mol ratio is varied between X = 0.04 and 0.16. However, for all samples the peak energy is far below the bandgap energy measured by photoluminescence excitation spectra, revealing a large Stokes-like shift of the InGaN emission. The temperature variation of the photoluminescence intensity yields an activation energy of 21 meV of the 2.6 eV emission and 67 meV of the 2.4 eV emission, respectively. The room temperature photoluminescence of fully strained multi quantum wells (x = 0.16) is a single line with a peak wavelength at about 510 nm.

Morphological and Optical Stability in Growth of Fluorescent SiC on Low Off-Axis Substrates

2013 ◽  
Vol 740-742 ◽  
pp. 19-22 ◽  
Author(s):  
Valdas Jokubavicius ◽  
Michl Kaiser ◽  
Philip Hens ◽  
Peter J. Wellmann ◽  
Rickard Liljedahl ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Vapor Phase ◽  
Growth Process ◽  
Room Temperature ◽  
Tantalum Foil ◽  
Photoluminescence Intensity ◽  
Room Temperature Photoluminescence ◽  
Optical Stability ◽  
Morphological Instabilities ◽  
Sublimation Growth

Fluorescent silicon carbide was grown using the fast sublimation growth process on low off-axis 6H-SiC substrates. In this case, the morphology of the epilayer and the incorporation of dopants are influenced by the Si/C ratio. Differently converted tantalum foils were introduced into the growth cell in order to change vapor phase stochiometry during the growth. Fluorescent SiC grown using fresh and fully converted tantalum foils contained morphological instabilities leading to lower room temperature photoluminescence intensity while an improved morphology and optical stability was achieved with partly converted tantalum foil. This work reflects the importance of considering the use of Ta foil in sublimation epitaxy regarding the morphological and optical stability in fluorescent silicon carbide.

Room Temperature Emission from Erbium Nanoparticles Embedded in a Silicon Matrix

1995 ◽  
Vol 405 ◽  
Author(s):  
A. Thilderkvist ◽  
J. Michel ◽  
S.-T. Ngiam ◽  
L. C. Kimerling ◽  
K. D. Kolenbrander
Keyword(s):  
Heat Treatment ◽  
Room Temperature ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Optically Active ◽  
Photoluminescence Intensity ◽  
Supersonic Expansion ◽  
Silicon Matrix ◽  
Room Temperature Photoluminescence ◽  
Expansion Technique

AbstractStrong room temperature photoluminescence emission from thin films of Er nanoparticles embedded in a matrix of silicon is reported. The Er nanoparticles were produced by a pulsed laser ablation supersonic expansion technique. After a heat treatment at 500°C in an Ar-atmosphere, intense Er-related luminescence appears at λ = 1.54 gim, characteristic of intra-4f emission from Er3÷. Only a 50% reduction in photoluminescence intensity is observed as the temperature increases from 4 K to 300 K. A photocarrier mediated process is responsible for the excitation of the optically active Er-centers.

Degradation in a Methyl-phenyl Co-Polymeric Polysilane for LED Applications

2003 ◽  
Vol 769 ◽  
Author(s):  
Asha Sharma ◽  
Deepak ◽  
Monica Katiyar ◽  
Satyendra Kumar ◽  
V. Chandrasekhar ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Weight ◽  
Light Source ◽  
Room Temperature ◽  
Light Exposure ◽  
Room Temperature Photoluminescence ◽  
Pl Spectrum ◽  
Pl Intensity ◽  
Methyl Phenyl

AbstractThe optical degradation of polysilane copolymer has been studied in spin cast thin films and solutions using light source of 325 nm wavelength. The room temperature photoluminescence (PL) spectrum of these films show a sharp emission at 368 nm when excited with a source of 325 nm. However, the PL intensity deteriorates with time upon light exposure. Further the causes of this degradation have been examined by characterizing the material for its transmission behaviour and changes occurring in molecular weight as analysed by GPC data.

Anomalous Room-Temperature Photoluminescence from Nanostrained MoSe2 Monolayers

ACS Photonics ◽  
2021 ◽  
Author(s):  
Tomojit Chowdhury ◽  
Kiyoung Jo ◽  
Surendra B. Anantharaman ◽  
Todd H. Brintlinger ◽  
Deep Jariwala ◽  
...  
Keyword(s):  
Room Temperature ◽  
Room Temperature Photoluminescence

The Study on Microstructural and Optical Properties of Nanocrystalline Germanium Films

2010 ◽  
Vol 663-665 ◽  
pp. 324-327
Author(s):  
Chao Song ◽  
Rui Huang
Keyword(s):  
Multilayer Structure ◽  
Room Temperature ◽  
Multilayer Film ◽  
Volume Fraction ◽  
Raman Scattering Spectroscopy ◽  
Force Microscopy ◽  
Room Temperature Photoluminescence ◽  
Atomic Force ◽  
Lower Volume Fraction ◽  
Lower Volume

The germanium film and Ge/Si multilayer structure were fabricated by magnetron sputtering technique on silicon substrate at temperatures of 500°C. Raman scattering spectroscopy measurements reveal that the nanocrystalline Ge occurs in both kinds of samples. Furthermore, from the atomic force microscopy (AFM) results, it is found that the grain size as well as spatially ordering distribution of the nc-Ge can be modulated by the Ge/Si multilayer structure. The room temperature photoluminescence was also observed in the samples. However, compared with that from the nc-Ge film, the intensity of PL from the nc-Ge/a-Si multilayer film becomes weaker, which is attributed to its lower volume fraction of crystallized component.

scholarly journals Enhanced Room‐Temperature Photoluminescence Quantum Yield in Morphology Controlled J‐Aggregates

2021 ◽  
pp. 1903080
Author(s):  
Surendra B. Anantharaman ◽  
Joachim Kohlbrecher ◽  
Gabriele Rainò ◽  
Sergii Yakunin ◽  
Thilo Stöferle ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Room Temperature ◽  
Room Temperature Photoluminescence ◽  
Photoluminescence Quantum Yield ◽  
J Aggregates

ROOM TEMPERATURE PHOTOLUMINESCENCE OF POLYCRYSTALLINE SIC PREPARED FROM CARBON-SATURATED SI MELT

2002 ◽  
Vol 16 (06n07) ◽  
pp. 1047-1051
Author(s):  
JIANPING MA ◽  
ZHIMING CHEN ◽  
GANG LU ◽  
MINGBIN YU ◽  
LIANMAO HANG ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Uv Light ◽  
X Ray Diffraction ◽  
X Ray ◽  
Room Temperature Photoluminescence ◽  
Composition And Structure ◽  
Light Excitation ◽  
Scanning Electron

Intense photoluminescence (PL) has been observed at room temperature from the polycrystalline SiC samples prepared from carbon-saturated Si melt at a temperature ranging from 1500 to 1650°C. Composition and structure of the samples have been confirmed by means of X-ray photoelectron spectroscopy, X-ray diffraction and scanning electron microscopy. PL measurements with 325 nm UV light excitation revealed that the room temperature PL spectrum of the samples consists of 3 luminescent bands, the peak energies of which are 2.38 eV, 2.77 eV and 3.06 eV, respectively. The 2.38 eV band is much stronger than the others. It is suggested that some extrinsic PL mechanisms associated with defect or interface states would be responsible to the intensive PL observed at room temperature.

Growth mechanism and characterization of ZnO nano-tubes synthesized using the hydrothermal-etching method

2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Yan Li ◽  
Chuan-Sheng Liu ◽  
Yun-Ling Zou
Keyword(s):  
Room Temperature ◽  
Morphological Analysis ◽  
Diffraction Field ◽  
X Ray Diffraction ◽  
X Ray ◽  
Room Temperature Photoluminescence ◽  
Etching Method ◽  
Nano Rods ◽  
Two Stages

AbstractZnO nano-tubes (ZNTs) have been successfully synthesized via a simple hydrothermal-etching method, and characterized by X-ray diffraction, field emission scanning electron microscopy and room temperature photoluminescence measurement. The as-synthesized ZNTs have a diameter of 500 nm, wall thickness of 20–30 nm, and length of 5 µm. Intensity of the plane (0002) diffraction peak, compared with that of plane (10$$ \bar 1 $$0) of ZNTs, is obviously lower than that of ZnO nano-rods. This phenomenon can be caused by the smaller cross section of plane (0002) of the nano-tubes compared with that of other morphologies. On basis of the morphological analysis, the formation process of nano-tubes can be proposed in two stages: hydrothermal growth and reaction etching process.

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