Spontaneous and Stimulated Recombination in the Nitrides

1996 ◽  
Vol 449 ◽  
Author(s):  
A. Hangleiter ◽  
F. Scholz ◽  
V. Härle ◽  
J. S. Im ◽  
G. Frankowsky
Keyword(s):  
Quantum Wells ◽  
Room Temperature ◽  
Optical Gain ◽  
Stimulated Emission ◽  
Time Resolved ◽  
Double Heterostructures ◽  
Bulk Gan ◽  
Photoluminescence Studies ◽  
Excitonic Effects ◽  
Time Resolved Photoluminescence

ABSTRACTBoth spontaneous and stimulated emission processes are essential ingredients for constructing a laser from the nitrides. Based on our picosecond time-resolved photoluminescence studies we show that spontaneous radiative recombination is strongly influenced by excitonic effects, both in bulk GaN and in quantum wells. Particularly in quantum wells, localization of excitons plays an important role. We have studied the optical gain spectra in GaInN/GaN and GaN/AlGaN double heterostructures and quantum wells, grown by LP-MOVPE, using the stripe excitation method. Both room temperature and low temperature measurements were performed. Based on our results, we discuss the physical mechanism of optical gain in the nitrides as well as consequences for laser operation. We show that localization or, equivalently, the formation of quantum dot like structures, governs the optical gain mechanism in the nitrides.

Time-resolved photoluminescence studies of InGaN/GaN single-quantum-wells at room temperature

1997 ◽  
Vol 71 (4) ◽  
pp. 425-427 ◽  
Author(s):  
C.-K. Sun ◽  
T.-L. Chiu ◽  
S. Keller ◽  
G. Wang ◽  
M. S. Minsky ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Room Temperature ◽  
Single Quantum ◽  
Time Resolved ◽  
Photoluminescence Studies ◽  
Time Resolved Photoluminescence

Time-resolved photoluminescence studies of stimulated emission and exciton dynamics in ZnSe/ZnS0.18Se0.82 superlattices

1994 ◽  
Vol 37 (4-6) ◽  
pp. 1133-1136
Author(s):  
C.J. Stevens ◽  
R.A. Taylor ◽  
J.F. Ryan ◽  
M. Dabbicco ◽  
M. Ferrara ◽  
...  
Keyword(s):  
Stimulated Emission ◽  
Time Resolved ◽  
Exciton Dynamics ◽  
Photoluminescence Studies ◽  
Time Resolved Photoluminescence

Epitaxial Growth and Luminescence Characterization of Si-based Double Heterostructures Light-emitting Diodes with Iron Disilicide Active Region

2006 ◽  
Vol 958 ◽  
Author(s):  
Takashi Suemasu ◽  
Cheng Li ◽  
Tsuyoshi Sunohara ◽  
Yuta Ugajin ◽  
Ken'ichi Kobayashi ◽  
...  
Keyword(s):  
Decay Time ◽  
Room Temperature ◽  
Time Resolved ◽  
Iron Disilicide ◽  
Light Emitting ◽  
Si Substrates ◽  
Carrier Recombination ◽  
Double Heterostructures ◽  
Time Resolved Photoluminescence

ABSTRACTWe have epitaxially grown Si/β-FeSi2/Si (SFS) structures with β-FeSi2 particles or β-FeSi2 continuous films on Si substrates by molecular beam epitaxy (MBE), and observed 1.6 μm electroluminescence (EL) at room temperature (RT). The EL intensity increases with increasing the number of β-FeSi2 layers. The origin of the luminescence was discussed using time-resolved photoluminescence (PL) measurements. It was found that the luminescence originated from two sources, one with a short decay time (τ∼10 ns) and the other with a long decay time (τ∼100 ns). The short decay time was due to carrier recombination in β-FeSi2, whereas the long decay time was due probably to a defect-related D1 line in Si.

Excitation-Wavelength Dependent and Time-Resolved Photoluminescence Studies of Europium Doped GaN Grown by Interrupted Growth Epitaxy (IGE)

2005 ◽  
Vol 866 ◽  
Author(s):  
Ei Ei Nyein ◽  
Uwe Hömmerich ◽  
Chanaka Munasinghe ◽  
Andrew J. Steckl ◽  
John M. Zavada
Keyword(s):  
Room Temperature ◽  
Growth Conditions ◽  
Excitation Wavelength ◽  
Time Resolved ◽  
Pl Intensity ◽  
Photoluminescence Studies ◽  
Two Peaks ◽  
Time Resolved Photoluminescence ◽  
Cycling Time ◽  
The Eu

AbstractThe emission properties of Eu doped GaN thin films prepared by interrupted growth epitaxy (IGE) were investigated through excitation-wavelength dependent and time-resolved photoluminescence (PL) studies. Under above-gap excitation (333-363 nm) large differences were observed in the Eu3+ PL intensity and spectral features as a function of Ga shutter cycling time. The overall strongest red Eu3+ PL intensity was obtained from a sample grown with a Gashutter cycling time of 20 minutes. The main Eu3+ emission line originating from 5D0→ 7F2 transition was composed of two peaks located at 620 nm and 622 nm, which varied in relative intensity depending on the growth conditions. The room-temperature emission lifetimes of the samples were non-exponential and varied from ∼50 νs to ∼200 νs (1/e lifetimes). Under resonant excitation at 471 nm (7F0→5D2) all samples exhibited nearly identical PL spectra independent of Ga shutter cycling time. Moreover, the Eu3+ PL intensities and lifetimes varied significantly less compared to above-gap excitation. The excitation wavelengths dependent PL results indicate the existence of different Eu3+ centers in GaN: Eu, which can be controlled by the Ga shutter cycling time.

scholarly journals Room-Temperature Time–Resolved Photoluminescence Studies of UV Emission from GaN/AlN Quantum Wells

2002 ◽  
Vol 743 ◽  
Author(s):  
Madalina Furis ◽  
Fei Chen ◽  
Alexander N. Cartwright ◽  
Hong Wu ◽  
William J. Schaff
Keyword(s):  
Quantum Wells ◽  
Room Temperature ◽  
Spatial Separation ◽  
Multiple Quantum ◽  
Carrier Injection ◽  
Time Resolved ◽  
Uv Emission ◽  
Time Resolved Photoluminescence ◽  
Temperature Time ◽  
Ir Light

ABSTRACTRoom temperature time-resolved photoluminescence (TRPL) studies of multiple quantum well (MQW) structures of the binaries GaN and AlN grown by molecular beam epitaxy are reported. The eventual application of these structures is for GaN intersubband IR light emitters. However, as an initial study, the structures are evaluated at UV to investigate materials parameters relevant to IR light emission. The nominally 0.9, 1.3 and 1.5 nm GaN quantum wells are clad by 6nm of AlN on top of a thick AlN buffer grown on sapphire. All samples consisted of 20 quantum wells. The observed peak energy of the emission spectrum is in excellent agreement with a model that includes the strong confinement present in these structures and the existence of the large built-in piezoelectric field and spontaneous polarization present inside the wells. Furthermore, consistent with screening of the in-well field as carriers are injected in the well, a clear blue shift of the emission is observed at short times after carrier injection. Subsequently, as the carriers recombine, the peak emission red-shifts and the screening of the field is reduced. Moreover, the observed lifetimes were energy dependent as should be expected from field dependent elongation of lifetimes due to spatial separation of the injected carriers. Specifically, the decay time at high energies can be fitted by a stretched exponential with a beta value of 0.8 which is consistent with carrier spatial separation. The lifetimes obtained from the fitting are of the order of 1ns, longer than the reported recombination lifetimes in similar GaN/AlGaN MQW's. On the low energy side of the PL feature the intensity time decay becomes exponential with lifetimes ranging from 3 to 10ns. The strong UV emission at room temperature makes these structures promising for UV emitters.

scholarly journals Time-resolved photoluminescence studies of annealed 1.3-μm GaInNAsSb quantum wells

2014 ◽  
Vol 9 (1) ◽  
pp. 81 ◽  
Author(s):  
Michal Baranowski ◽  
Robert Kudrawiec ◽  
Marcin Syperek ◽  
Jan Misiewicz ◽  
Tomas Sarmiento ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Time Resolved ◽  
Photoluminescence Studies ◽  
Time Resolved Photoluminescence
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