Femtosecond carrier dynamics in native and high resistivity iron-doped GaxIn1−xAs

2010 ◽  
Vol 107 (3) ◽  
pp. 033104 ◽  
Author(s):  
Suranjana Sengupta ◽  
Ingrid Wilke ◽  
Partha. S. Dutta
Keyword(s):  
Carrier Dynamics ◽  
High Resistivity ◽  
Iron Doped

Ultrafast carrier mobilities in high-resistivity iron-doped Ga0.69In0.31As photoconducting antennas

2009 ◽  
Vol 95 (21) ◽  
pp. 211102 ◽  
Author(s):  
Suranjana Sengupta ◽  
Ingrid Wilke ◽  
Partha. S. Dutta
Keyword(s):  
High Resistivity ◽  
Ultrafast Carrier ◽  
Iron Doped ◽  
Photoconducting Antennas

Ultrafast carrier dynamics in LT-GaAs doped with Si delta layers

2017 ◽  
Vol 31 (27) ◽  
pp. 1750195 ◽  
Author(s):  
D. I. Khusyainov ◽  
C. Dekeyser ◽  
A. M. Buryakov ◽  
E. D. Mishina ◽  
G. B. Galiev ◽  
...  
Keyword(s):  
Low Temperature ◽  
Carrier Lifetime ◽  
Carrier Dynamics ◽  
High Resistivity ◽  
Ultrafast Carrier Dynamics ◽  
Si Doping ◽  
Ultrafast Optical ◽  
Donor And Acceptor ◽  
Ultrafast Carrier ◽  
Lt Gaas

We characterized the ultrafast properties of LT-GaAs doped with silicon [Formula: see text]-layers and introduced delta-doping ([Formula: see text]-doping) as efficient method for enhancing the properties of GaAs-based structures which can be useful for terahertz (THz) antenna, ultrafast switches and other high frequency applications. Low temperature grown GaAs (LT-GaAs) became one of the most promising materials for ultrafast optical and THz devices due to its short carrier lifetime and high carrier mobility. Low temperature growth leads to a large number of point defects and an excess of arsenic. Annealing of LT-GaAs creates high resistivity through the formation of As-clusters, which appear due to the excess of arsenic. High resistivity is very important for THz antennas so that voltage can be applied without the risk of breakdown. With [Formula: see text]-Si doping, control of As-clusters is possible, since after annealing, clusters align in the plane where the [Formula: see text]-doping occurs. In this paper, we compare the properties of LT-GaAs-based planar structures with and without [Formula: see text]-Si doping and subsequent annealing. We used pump-probe transient reflectivity as a probe for ultrafast carrier dynamics in LT-GaAs. The results of the experiment were interpreted using the Ortiz model and show that the [Formula: see text]-Si doping increases deep donor and acceptor concentrations and decreases the photoinduced carrier lifetime as compared with LT-GaAs with same growth and annealing temperatures, but without doping.

Effect of deep traps on photo-generated carrier dynamics in high-resistivity CdTe

2000 ◽  
Vol 214-215 ◽  
pp. 212-215 ◽  
Author(s):  
Giorgio Ghislotti ◽  
Silvia M. Pietralunga ◽  
Luca Ripamonti
Keyword(s):  
Carrier Dynamics ◽  
High Resistivity ◽  
Deep Traps

JFET FOR COMPLETELY DEPLETED HIGH RESISTIVITY SILICON

1988 ◽  
Vol 49 (C4) ◽  
pp. C4-363-C4-366 ◽  
Author(s):  
V. RADEKA ◽  
P. REHAK ◽  
S. RESCIA ◽  
E. GATTI ◽  
A. LONGONI ◽  
...  
Keyword(s):  
High Resistivity ◽  
High Resistivity Silicon

Charge Carrier Dynamics in Nanostructured Tungsten Trioxide for Solar Driven Water Oxidation

2018 ◽  
Author(s):  
Sacha Corby ◽  
Laia Francas ◽  
Shababa Selim ◽  
Michael Sachs ◽  
Andreas Kafizas ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Water Oxidation ◽  
Tungsten Trioxide ◽  
Carrier Dynamics ◽  
Charge Carrier Dynamics

Pharmacokinetic Evaluation of 99mTc-radiolabeled Solid Lipid Nanoparticles and Chitosan Coated Solid Lipid Nanoparticles

2020 ◽  
Vol 20 (13) ◽  
pp. 1044-1052
Author(s):  
Nasrin Abbasi Gharibkandi ◽  
Sajjad Molavipordanjani ◽  
Jafar Akbari ◽  
Seyed Jalal Hosseinimehr
Keyword(s):  
Solid Lipid Nanoparticles ◽  
Lipid Nanoparticles ◽  
High Resistivity ◽  
Scanning Calorimetry ◽  
Liver Uptake ◽  
Solid Lipid ◽  
Transmission Electron ◽  
Main Portion ◽  
Pharmacokinetic Behavior

Background: Solid Lipid Nanoparticles (SLNs) possess unique in vivo features such as high resistivity, bioavailability, and habitation at the target site. Coating nanoparticles with polymers such as chitosan greatly affects their pharmacokinetic behavior, stability, tissue uptake, and controlled drug delivery. The aim of this study was to prepare and evaluate the biodistribution of 99mTc-labeled SLNs and chitosan modified SLNs in mice. Methods: 99mTc-oxine was prepared and utilized to radiolabel pre-papered SLNs or chitosan coated SLNs. After purification of radiolabeled SLNs (99mTc-SLNs) and radiolabeled chitosan-coated SLNs (99mTc-Chi-SLNs) using Amicon filter, they were injected into BALB/c mice to evaluate their biodistribution patterns. In addition, nanoparticles were characterized using Transmission Electron Microscopy (TEM), Fourier-transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-ray Powder Diffraction (XRD) and Dynamic Light Scattering (DLS). Results: 99mTc-oxine with high radiochemical purity (RCP~100%) and stability (RCP > 97% at 24 h) was used to provide 99mTc-SLNs and 99mTc-Chi-SLNs with high initial RCP (100%). TEM image and DLS data suggest 99mTc- SLNs susceptibility to aggregation. To that end, the main portion of 99mTc-SLNs radioactivity accumulates in the liver and intestines, while 99mTc-Chi-SLNs sequesters in the liver, intestines and kidneys. The blood radioactivity of 99mTc-Chi-SLNs was higher than that of 99mTc-SLNs by 7.5, 3.17 and 3.5 folds at 1, 4 and 8 h post-injection. 99mTc- Chi-SLNs uptake in the kidneys in comparison with 99mTc-SLNs was higher by 37.48, 5.84 and 11 folds at 1, 4 and 8h. Conclusion: The chitosan layer on the surface of 99mTc-Chi-SLNs reduces lipophilicity in comparison with 99mTc- SLNs. Therefore, 99mTc-Chi-SLNs are less susceptible to aggregation, which leads to their lower liver uptake and higher kidney uptake and blood concentration.

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