Confinement Barrier Induced Enhancement in Thermal Stability of the Optical Response of InAs/InGaAs/GaAs Submonolayer Quantum Dot Heterostuctures

Abstract:In this study the improvement in thermal stability of optical properties of InAs submonolayer quantum dot (SML QD) heterostructures is observed through incorporation of symmetric AlGaAs barrier layers. Low temperature photoluminescence (PL) spectra shows blue shift with less full width at half maxima, ascribe to the assimilation of AlGaAs barrier layers. The sample with confinement enhancing barrier shows the highest ground to ground transition energy with the lowest dot size distribution. Ex situ annealing of as grown samples, followed by PL analysis, confirms the improvement in thermal stability of optical behavior. For the samples with symmetric AlGaAs layer, annealing at higher temperatures under an inert condition can not change the downward transition energy effectively, whereas normal DWELL structures exhibits significant blue shift for the same.

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Analysis of luminescence, morphological and thermal behaviour of conjugated polymer/CdS electrospun nanofiber

Journal of Composite Materials ◽

10.1177/00219983211007531 ◽

2021 ◽

pp. 002199832110075

Author(s):

PS Umabharathi ◽

S Karpagam

Keyword(s):

Thermal Stability ◽

Composite Nanofibers ◽

Cadmium Sulphide ◽

Blue Shift ◽

Sem Analysis ◽

Tem Analysis ◽

Good Thermal Stability ◽

Ftir Technique ◽

Significant Blue Shift ◽

Thermal Stability Of

Electro spun composite nanofibers of three series were prepared using different polymers (P1, P2, P3) and cadmium sulphide (CdS). Organic polymers of carbazole based quinoline (P1), quinoxaline (P2), and pyrazine (P3) hybrid with inorganic CdS nanofibers were characterized by XRD and FTIR technique. Collective arrangement of spiderweb-like morphology was observed for all nanofibers. Deviations of absorption and photoluminescence were monitored and a significant blue shift was found after doping CdS and PVA. It was found that the changes in the PL spectra of polymers originated from the chemical interactions between polymer and CdS. The diameter of nanofibers was observed as 127-347 nm from SEM analysis and 66-213 nm from TEM analysis. Optimum thermal stability of the composite nanofibers was achieved up to 200 °C. Compared with pure polymers and CdS, present nanofibers were good thermal stability, apparent blue shift with bluish emission which is suitable for optoelectronics application.

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Thermal stability of quaternary alloy (InAlGaAs)-capped InAs/GaAs multilayer quantum dot heterostructures with variation in growth rate, barrier thickness, seed quantum dot monolayer coverage, and post-growth annealing

Applied Physics A ◽

10.1007/s00339-012-7521-2 ◽

2013 ◽

Vol 113 (1) ◽

pp. 215-220 ◽

Cited By ~ 4

Author(s):

A. Mandal ◽

U. Verma ◽

S. Chakrabarti

Keyword(s):

Thermal Stability ◽

Growth Rate ◽

Quantum Dot ◽

Quaternary Alloy ◽

Barrier Thickness ◽

Monolayer Coverage ◽

Thermal Stability Of

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Thermal Stability of Copper Films on CoW Barrier Layers

10.22443/rms.emc2020.1310 ◽

2021 ◽

Author(s):

Rúben Santos ◽

Keyword(s):

Thermal Stability ◽

Copper Films ◽

Barrier Layers ◽

Thermal Stability Of

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Thermal stability of laser-induced modified volumes in Si as studied by in situ and ex situ heating experiments

Microscopy ◽

10.1093/jmicro/dfy008 ◽

2018 ◽

Vol 67 (2) ◽

pp. 112-120

Author(s):

Hiroyasu Saka ◽

Hiroyuki Iwata ◽

Daisuke Kawaguchi

Keyword(s):

Electron Microscopy ◽

Thermal Stability ◽

Transmission Electron Microscopy ◽

Laser Beam ◽

Ex Situ ◽

Dislocation Theory ◽

Tail Region ◽

Transmission Electron ◽

Thermal Stability Of

Abstract Radiation of a permeable laser beam into Si induces considerable modification of structures. Thermal stability of the laser-induced modified volumes (LIMV’s) was studied comprehensively by means of in situ and ex situ heating experiments using transmission electron microscopy. The behavior in the tail region of a LIMV can be understood by dislocation theory, while that of a void formed at the very focus of a laser beam cannot be understood easily.

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