Band filling with free charge carriers in organometal halide perovskites

We have investigated a strong coupled system composed of a MAPbIxCl3-x perovskite film and aluminum conical nanopits array. The hybrid states formed by surface plasmons and free carriers, rather than the traditional excitons, is observed in both steady-state reflection measurements and transient absorption spectra. In particular, under near upper band resonant excitation, the bleaching signal from the band edge of uncoupled perovskite was completely separated into two distinctive bleaching signals of the hybrid system, which is clear evidence for the formation of strong coupling states between the free carrier–plasmon state. Besides this, a Rabi splitting up to 260 meV is achieved. The appearance of the lower bands can compensate for the poor absorption of the perovskite in the NIR region. Finally, we found that the lifetime of the free carrier–SP hybrid states is slightly shorter than that of uncoupled perovskite film, which can be caused by the ultrafast damping of the SPs modes. These peculiar features on the strong coupled hybrid states based on free charge carriers can open new perspectives for novel plasmonic perovskite solar cells.

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Deciphering the effect of traps on electronic charge transport properties of methylammonium lead tribromide perovskite

Science Advances ◽

10.1126/sciadv.abb6393 ◽

2020 ◽

Vol 6 (37) ◽

pp. eabb6393

Author(s):

Artem Musiienko ◽

Jindřich Pipek ◽

Petr Praus ◽

Mykola Brynza ◽

Eduard Belas ◽

...

Keyword(s):

Monte Carlo Simulation ◽

Charge Transport ◽

Transport Properties ◽

Critical Role ◽

Charge Carriers ◽

Electronic Charge ◽

Free Charge ◽

Optoelectronic Materials ◽

Halide Perovskites

Halide perovskites have undergone remarkable developments as highly efficient optoelectronic materials for a variety of applications. Several studies indicated the critical role of defects on the performance of perovskite devices. However, the parameters of defects and their interplay with free charge carriers remain unclear. In this study, we explored the dynamics of free holes in methylammonium lead tribromide (MAPbBr3) single crystals using the time-of-flight (ToF) current spectroscopy. By combining ToF spectroscopy and Monte Carlo simulation, three energy states were detected in the bandgap of MAPbBr3. In addition, we found the trapping and detrapping rates of free holes ranging from a few microseconds to hundreds of microseconds. Contrary to previous studies, we revealed a strong detrapping activity of traps. We showed that these traps substantially affect the transport properties of MAPbBr3, including mobility and mobility-lifetime product. Our results provide an insight on charge transport properties of perovskite semiconductors.

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Laser Engineering of Barrier Structures Based on Solid Solution ZnCdHgTe.

MRS Proceedings ◽

10.1557/proc-719-f8.35 ◽

2002 ◽

Vol 719 ◽

Author(s):

Galina Khlyap

Keyword(s):

Room Temperature ◽

Film Surface ◽

Charge Carriers ◽

Barrier Structure ◽

Free Charge ◽

Current Voltage ◽

Capacitance Voltage ◽

Laser Engineering ◽

Charged Defects ◽

Epilayer Surface

AbstractRoom-temperature electric investigations carried out in CO2-laser irradiated ZnCdHgTe epifilms revealed current-voltage and capacitance-voltage dependencies typical for the metal-semiconductor barrier structure. The epilayer surface studies had demonstrated that the cell-like relief has replaced the initial tessellated structure observed on the as-grown samples. The detailed numerical analysis of the experimental measurements and morphological investigations of the film surface showed that the boundaries of the cells formed under the laser irradiation are appeared as the regions of accumulation of derived charged defects of different type of conductivity supplying free charge carriers under the applied electric field.

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Highly Emissive Halide Perovskite Nanocrystals: From Lead to Lead-Free

CrystEngComm ◽

10.1039/d1ce00344e ◽

2021 ◽

Author(s):

Chunlong Li ◽

Jie Li ◽

Zhengping Li ◽

Huayong Zhang ◽

Yangyang Dang ◽

...

Keyword(s):

Charge Carriers ◽

Lead Free ◽

Quantum Yields ◽

Local Management ◽

Perovskite Nanocrystals ◽

Halide Perovskites ◽

Halide Perovskite

Nanostructured halide perovskites have highly yielded record LEDs due to their higher versatility in the local management of charge carriers, which has enabled photoluminescence quantum yields (PLQYs) close to 100%....

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Dielectric relaxation of free charge carriers in some fluorite-type solid solutions

Physica B Condensed Matter ◽

10.1016/s0921-4526(97)00488-2 ◽

1998 ◽

Vol 244 ◽

pp. 201-206 ◽

Cited By ~ 9

Author(s):

E.F. Hairetdinov ◽

N.F. Uvarov ◽

J.-M. Reau ◽

P. Hagenmuller

Keyword(s):

Dielectric Relaxation ◽

Solid Solutions ◽

Charge Carriers ◽

Free Charge ◽

Fluorite Type

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Properties of Excitons and Photogenerated Charge Carriers in Metal Halide Perovskites

Advanced Materials ◽

10.1002/adma.201806671 ◽

2019 ◽

Vol 31 (47) ◽

pp. 1806671 ◽

Cited By ~ 34

Author(s):

Ying Jiang ◽

Xiao Wang ◽

Anlian Pan

Keyword(s):

Metal Halide ◽

Charge Carriers ◽

Halide Perovskites

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Optical generation of free charge carriers in nanocrystalline tin oxide for gas sensor application

Microelectronic Engineering ◽

10.1016/j.mee.2011.05.029 ◽

2012 ◽

Vol 90 ◽

pp. 44-46 ◽

Cited By ~ 2

Author(s):

Irina A. Zhurbina ◽

Victor Yu. Timoshenko

Keyword(s):

Gas Sensor ◽

Tin Oxide ◽

Charge Carriers ◽

Free Charge ◽

Sensor Application ◽

Optical Generation

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Ferromagnetic Behaviors in Fe-Doped NiO Nanofibers Synthesized by Electrospinning Method

Journal of Nanomaterials ◽

10.1155/2013/252593 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 4

Author(s):

Yi-Dong Luo ◽

Yuan-Hua Lin ◽

Xuehui Zhang ◽

Deping Liu ◽

Yang Shen ◽

...

Keyword(s):

Room Temperature ◽

Doping Concentration ◽

Double Exchange ◽

Host Lattice ◽

Charge Carriers ◽

Fe Doping ◽

Free Charge ◽

Ferromagnetic Properties ◽

Electrospinning Method ◽

Fe Ions

Ni1−xFexOnanofibers with different Fe doping concentration have been synthesized by electrospinning method. An analysis of the phase composition and microstructure shows that Fe doping has no influence on the crystal structure and morphology of NiO nanofibers, which reveals that the doped Fe ions have been incorporated into the NiO host lattice. Pure NiO without Fe doping is antiferromagnetic, yet all the Fe-doped NiO nanofiber samples show obvious room-temperature ferromagnetic properties. The saturation magnetization of the nanofibers can be enhanced with increasing Fe doping concentration, which can be ascribed to the double exchange mechanism through the doped Fe ions and free charge carriers. In addition, it was found that the diameter of nanofibers has significant impact on the ferromagnetic properties, which was discussed in detail.

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