How photon pump fluence changes the charge carrier relaxation mechanism in an organic–inorganic hybrid lead triiodide perovskite

2016 ◽  
Vol 18 (39) ◽  
pp. 27090-27101 ◽  
Author(s):  
Piotr Piatkowski ◽  
Boiko Cohen ◽  
Samrana Kazim ◽  
Shahzada Ahmad ◽  
Abderrazzak Douhal
Keyword(s):  
Thin Film ◽  
Charge Carrier ◽  
Transient Absorption ◽  
Relaxation Mechanism ◽  
Relaxation Dynamics ◽  
Polycrystalline Thin Film ◽  
Carrier Relaxation ◽  
Inorganic Hybrid ◽  
Femtosecond Transient Absorption ◽  
Carrier Relaxation Dynamics

The fluence dependent charge carrier relaxation dynamics in a FAPbI3 polycrystalline thin film were measured using femtosecond transient absorption and terahertz spectroscopies.

scholarly journals Ultrafast relaxation dynamics in bimetallic plasmonic catalysts

Nanoscale ◽  
2020 ◽  
Vol 12 (18) ◽  
pp. 10284-10291 ◽  
Author(s):  
Sangwan Sim ◽  
Alyssa Beierle ◽  
Philip Mantos ◽  
Steven McCrory ◽  
Rohit P. Prasankumar ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Au Nanoparticles ◽  
Relaxation Dynamics ◽  
Carrier Relaxation ◽  
Ultrafast Relaxation ◽  
Carrier Relaxation Dynamics

The charge carrier relaxation dynamics of bimetallic plasmonic catalysts Au/Ni and Au/Pt is significantly different from that of pure Au nanoparticles, which will impact their performance.

scholarly journals Carrier relaxation dynamics in defect states of epitaxial GaN/AlN/Si using ultrafast transient absorption spectroscopy

RSC Advances ◽  
2015 ◽  
Vol 5 (102) ◽  
pp. 83969-83975 ◽  
Author(s):  
Palak Dugar ◽  
Mahesh Kumar ◽  
Shibin Krishna T. C. ◽  
Neha Aggarwal ◽  
Govind Gupta
Keyword(s):  
Absorption Spectroscopy ◽  
Transient Absorption ◽  
Transient Absorption Spectroscopy ◽  
Relaxation Dynamics ◽  
Defect States ◽  
Carrier Relaxation ◽  
Ultrafast Transient Absorption ◽  
Defect Levels ◽  
Carrier Relaxation Dynamics ◽  
Ultrafast Transient Absorption Spectroscopy

Carrier relaxation dynamics through the defect levels in an epitaxial GaN/AlN/Si have been analysed on the femto–picosecond timescale, using ultrafast-transient absorption spectroscopy.

scholarly journals Charge Carrier Relaxation in Colloidal FAPbI3 Nanostructures Using Global Analysis

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1897
Author(s):  
Carolina Villamil Franco ◽  
Benoît Mahler ◽  
Christian Cornaggia ◽  
Thomas Gustavsson ◽  
Elsa Cassette
Keyword(s):  
Charge Carrier ◽  
Transient Absorption ◽  
Global Analysis ◽  
High Energy ◽  
Analysis Method ◽  
Relaxation Dynamics ◽  
Lead Iodide ◽  
Carrier Relaxation ◽  
Spectral Lineshape ◽  
High Energy Tail

We study the hot charge carrier relaxation process in weakly confined hybrid lead iodide perovskite colloidal nanostructures, FAPbI3 (FA = formaminidium), using femtosecond transient absorption (TA). We compare the conventional analysis method based on the extraction of the carrier temperature (Tc) by fitting the high-energy tail of the band-edge bleach with a global analysis method modeling the continuous evolution of the spectral lineshape in time using a simple sequential kinetic model. This practical approach results in a more accurate way to determine the charge carrier relaxation dynamics. At high excitation fluence (density of charge carriers above 1018 cm−3), the cooling time increases up to almost 1 ps in thick nanoplates (NPs) and cubic nanocrystals (NCs), indicating the hot phonon bottleneck effect. Furthermore, Auger heating resulting from the multi-charge carrier recombination process slows down the relaxation even further to tens and hundreds of picoseconds. These two processes could only be well disentangled by analyzing simultaneously the spectral lineshape and amplitude evolution.

Synthesis and characterization of Cu x S nanoparticles. Nature of the infrared band and charge-carrier dynamics

2000 ◽  
Vol 72 (1-2) ◽  
pp. 101-117 ◽  
Author(s):  
M. C. Brelle ◽  
C. L. Torres-Martinez ◽  
J. C. McNulty ◽  
R. K. Mehra ◽  
J. Z. Zhang
Keyword(s):  
Charge Carrier ◽  
Transient Absorption ◽  
Electronic Absorption Spectra ◽  
Casein Hydrolysate ◽  
Early Time ◽  
Steady Increase ◽  
Relaxation Dynamics ◽  
Infrared Band ◽  
Additional Absorption ◽  
Femtosecond Transient Absorption

CuxS (x = 1,2) nanoparticles have been synthesized utilizing different capping molecules including polyethyleneglycol (PEG), polyvinylpyrrolidone (PVP), casein hydrolysate-enzymatic (CAS), and bovine serum albumin (BSA). The ground-state electronic absorption spectra of the CuxS nanoparticles show three distinct types of CuxS formed: a green type assigned as crystalline CuS, and two brown types assigned as crystalline Cu2S and amorphous Cu2S. The brown types exhibit a steady increase in absorption toward shorter wavelengths starting at around 650 nm, while the green type shows the same steady increase in absorption, but with an additional absorption band in the infrared (IR). The IR band is attributed to an electron-acceptor state lying within the bandgap. ESR measurements of free Cu(II) ions in solution for all samples show the presence of Cu(II) in the brown amorphous samples, but not in the green or brown crystalline samples. Ultrafast dynamics of photoinduced electrons have been measured for all samples using femtosecond-transient absorption/bleach spectroscopy. In all brown Cu2S samples studied, the early time-transient profiles feature a pulse-width-limited (<150 fs) rise followed by a fast decay (1.1 ps) and a slow decay (>80 ps). These decay dynamics were found to be independent of pump power and stabilizing agent. The fast 1.1 ps decay is attributed to charge carrier trapping, while the long decay may be due to either recombination or deep trapping of the charge carriers. The green CuxS samples studied showed interesting power-dependent behavior. At low excitation intensities, the green CuxS samples showed a transient bleach signal, while at high intensities, a transient absorption signal has been observed. The increased transient absorption over bleach at high intensities is attributed to trap-state saturation. A kinetic model has been developed to account for the main features of the electronic relaxation dynamics.

scholarly journals Effect of Zn(O,S) buffer layer thickness on charge carrier relaxation dynamics of CuInSe 2 solar cell

Solar Energy ◽  
2015 ◽  
Vol 115 ◽  
pp. 396-404 ◽  
Author(s):  
Juan Sun ◽  
Venkatram Nalla ◽  
Mai Nguyen ◽  
Yi Ren ◽  
Sing Yang Chiam ◽  
...  
Keyword(s):  
Solar Cell ◽  
Charge Carrier ◽  
Buffer Layer ◽  
Layer Thickness ◽  
Relaxation Dynamics ◽  
Carrier Relaxation ◽  
Buffer Layer Thickness ◽  
Carrier Relaxation Dynamics
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