Controlling Growth of InAs/GaAs Self-Assembled Quantum Dots to Give 1.3 μm Room Temperature Emission

1999 ◽  
Vol 571 ◽  
Author(s):  
Surama Malik ◽  
Philip Siverns ◽  
David Childs ◽  
Christine Roberts ◽  
Jean-Michel Hartmann ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Excited States ◽  
Room Temperature ◽  
Growth Parameters ◽  
High Growth ◽  
Growth Conditions ◽  
Time Resolved ◽  
Confining Potential ◽  
Decay Times ◽  
Self Assembled

ABSTRACTWe have investigated the extent to which the emission wavelength of self-assembled InAs/GaAs quantum dots can be controlled by growth parameters using conventional solid source MBE. Changing from conventionally high growth rates to a very low growth rate (LGR) and a relatively high substrate temperature, tunes the photoluminescence (PL) emission from 1.1 μm to 1.3 μm at room temperature. Atomic force micrographs obtained from uncapped samples reveal that these LGRQDs are larger, lower in density and extremely uniform in size. The improved size uniformity is reflected in the reduction of the PL linewidth from 78 meV to 22 meV. Under conditions of high excitation, emission from the ground and two excited states each separated by ∼70 meV is observed. This implies a parabolic confining potential. Time resolved photoluminescence (TRPL) measurements of dots grown under the various growth conditions yield radiative lifetimes which reflect the depth of the confining potential. A comparison of the decay times measured for the excited states show that the relaxation of carriers within the dots cannot be ascribed to phonon effects.

State filling and time-resolved photoluminescence of excited states inInxGa1−xAs/GaAs self-assembled quantum dots

1996 ◽  
Vol 54 (16) ◽  
pp. 11548-11554 ◽  
Author(s):  
S. Raymond ◽  
S. Fafard ◽  
P. J. Poole ◽  
A. Wojs ◽  
P. Hawrylak ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Excited States ◽  
Time Resolved ◽  
Self Assembled ◽  
Time Resolved Photoluminescence ◽  
State Filling

Well-defined excited states of self-assembled InAs∕InAlGaAs quantum dots on InP (001)

2005 ◽  
Vol 87 (5) ◽  
pp. 053102 ◽  
Author(s):  
Jin Soo Kim ◽  
Jin Hong Lee ◽  
Sung Ui Hong ◽  
Ho-Sang Kwack ◽  
Byung Seok Choi ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Excited States ◽  
Self Assembled

scholarly journals Photooxidation and Photobleaching of Single CdSe/ZnS Quantum Dots Probed by Room-Temperature Time-Resolved Spectroscopy

2001 ◽  
Vol 105 (35) ◽  
pp. 8281-8284 ◽  
Author(s):  
Wilfried G. J. H. M. van Sark ◽  
Patrick L. T. M. Frederix ◽  
Dave J. Van den Heuvel ◽  
Hans C. Gerritsen ◽  
Ageeth A. Bol ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Room Temperature ◽  
Time Resolved ◽  
Time Resolved Spectroscopy ◽  
Temperature Time

Mode assignment of excited states in self-assembled InAs/GaAs quantum dots

1998 ◽  
Vol 58 (11) ◽  
pp. 7181-7187 ◽  
Author(s):  
Susumu Noda ◽  
Tomoki Abe ◽  
Masatoshi Tamura
Keyword(s):  
Quantum Dots ◽  
Excited States ◽  
Self Assembled ◽  
Mode Assignment

Excited states and selection rules in self-assembled InAs/GaAs quantum dots

1999 ◽  
Vol 60 (4) ◽  
pp. R2185-R2188 ◽  
Author(s):  
I. E. Itskevich ◽  
M. S. Skolnick ◽  
D. J. Mowbray ◽  
I. A. Trojan ◽  
S. G. Lyapin ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Excited States ◽  
Selection Rules ◽  
Self Assembled

Self-assembled quantum dots and nanoholes by molecular beam epitaxial growth and atomically precise in situ etching

2002 ◽  
Vol 722 ◽  
Author(s):  
S. Kiravittaya ◽  
R. Songmuang ◽  
O. G. Schmidt
Keyword(s):  
Quantum Dots ◽  
Molecular Beam ◽  
Flat Surface ◽  
Local Strain ◽  
Growth Conditions ◽  
Etching Depth ◽  
Molecular Beam Epitaxial ◽  
Self Assembled ◽  
Molecular Beam Epitaxial Growth

AbstractEnsembles of homogeneous self-assembled quantum dots (QDs) and nanoholes are fabricated using molecular beam epitaxy in combination with atomically precise in situ etching. Self-assembled InAs QDs with height fluctuations of ±5% were grown using a very low indium growth rate on GaAs (001) substrate. If these dots are capped with GaAs at low temperature, strong room temperature emission at 1.3 νm with a linewidth of 21 meV from the islands is observed. Subsequently, we fabricate homogeneous arrays of nanoholes by in situ etching the GaAs surface of the capped InAs QDs with AsBr3. The depths of the nanoholes can be tuned over a range of 1-6 nm depending on the nominal etching depth and the initial capping layer thickness. We appoint the formation of nanoholes to a pronounced selectivity of the AsBr3 to local strain fields. The holes can be filled with InAs again such that an atomically flat surface is recovered. QDs in the second layer preferentially form at those sites, where the holes were initially created. Growth conditions for the second InAs layer can be chosen in such a way that lateral QD molecules form on a flat surface.

scholarly journals Влияние условий роста и уровня легирования на кинетику люминесценции слоев Ge : Sb, выращенных на кремнии

2020 ◽  
Vol 54 (7) ◽  
pp. 685
Author(s):  
Д.В. Юрасов ◽  
Н.А. Байдакова ◽  
А.Н. Яблонский ◽  
А.В. Новиков
Keyword(s):  
Doping Level ◽  
Room Temperature ◽  
Carrier Lifetime ◽  
Growth Conditions ◽  
Published Data ◽  
Rapid Thermal Anneal ◽  
Time Resolved ◽  
Light Emitting ◽  
Pl Intensity ◽  
Time Resolved Photoluminescence

Light-emitting properties of Ge-on-Si(001) layers doped by Sb were studied by stationary and time-resolved photoluminescence (PL) at room temperature. It was obtained that the PL intensity of n-Ge/Si(001) structures is maximized when the doping level is close to the equilibrium solubility of Sb in Ge (~1019 cm-3) which is in accordance with the previously published data. Time-resolved studies of the direct-related PL signal have shown that both the donor density and the growth conditions of doped layer, in particular, the growth temperature influence the PL kinetics. It was obtained that the increase of doping level leads to the decrease of the characteristic carrier lifetime. Moreover, usage of low growth temperatures which is needed to form the doped n-Ge layers also results in shortening of the carrier lifetime as compared with Ge layers grown at high temperatures. It was found that rapid thermal anneal at proper conditions could partially compensate the above mentioned detrimental effects and lead to the increase of both the PL intensity and carrier lifetime.

On Applicability of Time-Resolved Optical Techniques for Characterization of Differently Grown 3C-SiC Crystals and Heterostructures

2012 ◽  
Vol 711 ◽  
pp. 159-163 ◽  
Author(s):  
Patrik Ščajev ◽  
Pavels Onufrijevs ◽  
Georgios Manolis ◽  
Mindaugas Karaliūnas ◽  
Saulius Nargelas ◽  
...  
Keyword(s):  
Room Temperature ◽  
Defect Density ◽  
Growth Conditions ◽  
Free Carrier ◽  
Band Edge Emission ◽  
Free Carrier Absorption ◽  
Free Standing ◽  
Optical Techniques ◽  
Time Resolved ◽  
Photoelectrical Properties

We applied a number of time-resolved optical techniques for investigation of optical and photoelectrical properties of cubic SiC grown by different technologies on different substrates. The excess carriers were injected by a short laser pulse and their dynamics was monitored by free-carrier absorption, light-induced transient grating, and photoluminescence techniques in a wide excitation range. Combining an optical and electrical probe beam delay, we found that free carrier lifetimes in differently grown layers vary from few ns up to 20 μs. Temperature dependences of carrier diffusivity and lifetime revealed a pronounced carrier trapping in thin sublimation grown layers. In free-standing layers and thick sublimation layers, the ambipolar mobility was found the highest (120 cm2/Vs at room temperature). A linear correlation between the room-temperature band edge emission and carrier lifetime in differently grown layers was attributed to defect density, strongly dependent on the used growth conditions.

Excited states of modified oxygen-deficient centers and Si quantum dots in Gd-implanted silica glasses: Emission dynamics and lifetime distributions

2021 ◽  
Author(s):  
Anatoly Zatsepin ◽  
Yulia Kuznetsova ◽  
Elena Trofimova ◽  
Vladimir A Pustovarov
Keyword(s):  
Quantum Dots ◽  
Ion Implantation ◽  
Excited States ◽  
Lifetime Distributions ◽  
Time Resolved ◽  
Silica Glasses ◽  
Pulsed Cathodoluminescence ◽  
Si Quantum Dots

The emission centers and excited states characteristics in silica glasses implanted with Gd ions were studied by time-resolved pulsed cathodoluminescence. It was found that in the process of ion implantation,...

Photoluminescence and Scintillation Properties of Pb2+ Based Quantum Dots in CsCI Host Crystal

1994 ◽  
Vol 348 ◽  
Author(s):  
M. Nikl ◽  
K. Nitsch ◽  
I. Dafinei ◽  
P. Lecoq ◽  
G.P. Pazzi ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Steady State ◽  
Room Temperature ◽  
Emission Spectra ◽  
Emission Peak ◽  
Kinetic Properties ◽  
Host Crystal ◽  
Exponential Behavior ◽  
Decay Times ◽  
Single Exponential

ABSTRACTThe spectral and kinetic properties of photoluminescence of Pb2+ aggregated phase in CsC1 host, together with scintillation characteristics of CsCI:Pb crystals, are reported in the 10 - 300 K temperature range. Absorption, steady-state excitation and emission spectra of Pb2+ phase in CsCI host are similar to those of CsPbCl3 bulk crystal (emission peak at 419 nm at 10 K). The decay of the 421 nm luminescence of the Pb2+ phase in CsCl shows single exponential behavior with extremely short decay time of 40 ps at 421 nm and 10 K,which is considerably shorter than the decay times found in the decay of CsPbCl3 bulk emission (0.45, 2.8 and 12 ns at 418 nm and 10 K). In the scintillation decay of CsCI:Pb, two components with 0.95-1 ns and 2-3 ns decay times were found and no slower component is present at room temperature.

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