Effects of Crystal Morphology on the Hot-Carrier Dynamics in Mixed-Cation Hybrid Lead Halide Perovskites

Ultrafast pump-probe spectroscopies have proved to be an important tool for the investigation of charge carriers dynamics in perovskite materials providing crucial information on the dynamics of the excited carriers, and fundamental in the development of new devices with tailored photovoltaic properties. Fast transient absorbance spectroscopy on mixed-cation hybrid lead halide perovskite samples was used to investigate how the dimensions and the morphology of the perovskite crystals embedded in the capping (large crystals) and mesoporous (small crystals) layers affect the hot-carrier dynamics in the first hundreds of femtoseconds as a function of the excitation energy. The comparative study between samples with perovskite deposited on substrates with and without the mesoporous layer has shown how the small crystals preserve the temperature of the carriers for a longer period after the excitation than the large crystals. This study showed how the high sensitivity of the time-resolved spectroscopies in discriminating the transient response due to the different morphology of the crystals embedded in the layers of the same sample can be applied in the general characterization of materials to be used in solar cell devices and large area modules, providing further and valuable information for the optimization and enhancement of stability and efficiency in the power conversion of new perovskite-based devices.

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Applications of an amorphous silicon-based area detector for high-resolution, high-sensitivity and fast time-resolved pair distribution function measurements

Journal of Applied Crystallography ◽

10.1107/s0021889807007856 ◽

2007 ◽

Vol 40 (3) ◽

pp. 463-470 ◽

Cited By ~ 147

Author(s):

Peter J. Chupas ◽

Karena W. Chapman ◽

Peter L. Lee

Keyword(s):

Distribution Function ◽

Amorphous Silicon ◽

Pair Distribution Function ◽

High Sensitivity ◽

High Energy ◽

Scattering Data ◽

Fast Time ◽

Large Area ◽

Nickel Metal ◽

Time Resolved

The application of a large-area (41 × 41 cm, 2048 × 2048 or 1024 × 1024 pixel) high-sensitivity (detective quantum efficiency > 65%) fast-readout (up to 7.5 or 30 Hz) flat-panel detector based on an amorphous silicon array system to the collection of high-energy X-ray scattering data for quantitative pair distribution function (PDF) analysis is evaluated and discussed. Data were collected over a range of exposure times (0.13 s–7 min) for benchmark PDF samples: crystalline nickel metal and amorphous silica (SiO2). The high real-space resolution of the resultant PDFs (withQmaxup to ∼40 Å−1) and the high quality of fits to data [RNi(0.13s)= 10.5%,RNi(1.3s)= 6.3%] obtained in short measurement times indicate that this detector is well suited to studies of materials disorder. Further applications of the detector to locate weakly scattering H2molecules within the porous Prussian blue system, {\rm Mn}^{\rm II}_{\,3}[CoIII(CN)6]2·xH2, and to follow thein situreduction of PtIVO2to Pt0at 30 Hz, confirm the high sensitivity of the detector and demonstrate a new potential for fast time-resolved studies.

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Hot carrier dynamics and electron-optical phonon coupling in photoexcited graphene via time-resolved ultrabroadband terahertz spectroscopy

Physical Review Research ◽

10.1103/physrevresearch.3.043143 ◽

2021 ◽

Vol 3 (4) ◽

Author(s):

Sho Ikeda ◽

Chiko Otani ◽

Masatsugu Yamashita

Keyword(s):

Optical Phonon ◽

Terahertz Spectroscopy ◽

Carrier Dynamics ◽

Phonon Coupling ◽

Time Resolved ◽

Hot Carrier

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Hot Carrier Dynamics in Lead Halide Perovskites: Mobility and Carrier-Phonon Coupling

10.29363/nanoge.hopv.2019.108 ◽

2019 ◽

Author(s):

Andrés Burgos-Caminal ◽

Aurélien Willauer ◽

Ahmad Ajdar Zadeh ◽

Jacques-E. Moser

Keyword(s):

Carrier Dynamics ◽

Phonon Coupling ◽

Hot Carrier ◽

Halide Perovskites ◽

Lead Halide

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Ultrafast hot carrier dynamics of ZrTe5 from time-resolved optical reflectivity

Physical Review B ◽

10.1103/physrevb.99.125141 ◽

2019 ◽

Vol 99 (12) ◽

Cited By ~ 4

Author(s):

Xiu Zhang ◽

Hai-Ying Song ◽

X. C. Nie ◽

Shi-Bing Liu ◽

Yang Wang ◽

...

Keyword(s):

Carrier Dynamics ◽

Time Resolved ◽

Hot Carrier ◽

Optical Reflectivity

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TIME-RESOLVED RAMAN STUDIES OF NON-EQUILIBRIUM EXCITATIONS IN GaAs-AlAs AND GaAs-AlxGa1−xAs MULTIPLE QUANTUM WELL STRUCTURES

Modern Physics Letters B ◽

10.1142/s0217984992000788 ◽

1992 ◽

Vol 06 (12) ◽

pp. 703-716 ◽

Cited By ~ 2

Author(s):

K. T. TSEN

Keyword(s):

Quantum Well ◽

Multiple Quantum Well ◽

Carrier Dynamics ◽

Multiple Quantum ◽

Electron Hole ◽

Photoexcited Electron ◽

Time Resolved ◽

Quantum Well Structures ◽

Hot Carrier ◽

Electron Hole Plasma

Recent experimental results obtained from time-resolved Raman studies in GaAs-AlAs and GaAs-Al x Ga 1−x As multiple quantum well structures are reviewed. Particular emphasis is made on (1) electron-phonon and phonon-phonon interactions and their association with the hot-phonon effects in the hot-carrier dynamics of multiple quantum well structures; and (2) the transport properties of photoexcited electron-hole plasma and excitons in semiconductor multiple quantum well structures.

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Design of a Sensitive Balloon Sensor for Safe Human–Robot Interaction

Sensors ◽

10.3390/s21062163 ◽

2021 ◽

Vol 21 (6) ◽

pp. 2163

Author(s):

Dongjin Kim ◽

Seungyong Han ◽

Taewi Kim ◽

Changhwan Kim ◽

Doohoe Lee ◽

...

Keyword(s):

High Performance ◽

Strain Sensor ◽

High Sensitivity ◽

Human Robot Interaction ◽

Large Area ◽

Tactile Sensors ◽

Robot Interaction ◽

Mechanical Crack ◽

Flexible Strain Sensor ◽

Contact Sensing

As the safety of a human body is the main priority while interacting with robots, the field of tactile sensors has expanded for acquiring tactile information and ensuring safe human–robot interaction (HRI). Existing lightweight and thin tactile sensors exhibit high performance in detecting their surroundings. However, unexpected collisions caused by malfunctions or sudden external collisions can still cause injuries to rigid robots with thin tactile sensors. In this study, we present a sensitive balloon sensor for contact sensing and alleviating physical collisions over a large area of rigid robots. The balloon sensor is a pressure sensor composed of an inflatable body of low-density polyethylene (LDPE), and a highly sensitive and flexible strain sensor laminated onto it. The mechanical crack-based strain sensor with high sensitivity enables the detection of extremely small changes in the strain of the balloon. Adjusting the geometric parameters of the balloon allows for a large and easily customizable sensing area. The weight of the balloon sensor was approximately 2 g. The sensor is employed with a servo motor and detects a finger or a sheet of rolled paper gently touching it, without being damaged.

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Urinary gonadotropin measurements by enhanced luminometric assays (LIA) for the evaluation of pubertal development

Journal of Pediatric Endocrinology and Metabolism ◽

10.1515/jpem-2020-0598 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

And Demir ◽

Adem Aydın ◽

Atilla Büyükgebiz ◽

Ulf-Håkan Stenman ◽

Matti Hero

Keyword(s):

Healthy Subjects ◽

Reliable Method ◽

Pubertal Development ◽

High Sensitivity ◽

Tanner Stage ◽

Time Resolved ◽

Stage 1 ◽

Sensitive Detection Technique ◽

Serum And Urine

Abstract Objectives Determination of LH in urine has proved to be a reliable method for evaluation of pubertal development. The human LH assay based on time-resolved immunofluorometric (IFMA) technology (AutoDELFIA, PerkinElmer, Wallac) has been found to be suitable for this purpose thanks to its high sensitivity but other assays have not been evaluated. We have analyzed our data obtained by another potentially sensitive detection technique, enhanced luminometric assay (LIA) with the objective of finding a viable alternative to IFMA since these may not be available in the future. Methods LIA was used to measure LH and FSH in serum and urine samples from 100 healthy subjects of each Tanner stage and both genders, whose pubertal development has been determined. Results Urinary gonodotropin concentrations measured by LIA correlated well with Tanner stage [(r=0.93 for girls, r=0.81 for boys; p<0.01 for LH) and (r=0.81 for girls, r=0.73 for boys; p<0.01 for FSH)]. LIA determinations revealed the increase in U-LH concentrations during the transition from Tanner stage 1–2 in both girls and boys (p<0.001), whereas U-FSH and S-LH were able to detect the increase from Tanner stage 1–2 only in boys or girls, respectively (both p<0.001). Conclusions Measurement of urinary gonadotropin concentrations by LIA may be useful for the evaluation of overall pubertal development and also in the detection of transition from prepuberty to puberty.

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