Charge transport in organic crystals: Critical role of correlated fluctuations unveiled by analysis of Feynman diagrams

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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Charge Transport in Organic Crystals: Role of Disorder and Topological Connectivity

Journal of the American Chemical Society ◽

10.1021/ja104380c ◽

2010 ◽

Vol 132 (33) ◽

pp. 11702-11708 ◽

Cited By ~ 131

Author(s):

Thorsten Vehoff ◽

Björn Baumeier ◽

Alessandro Troisi ◽

Denis Andrienko

Keyword(s):

Charge Transport ◽

Organic Crystals ◽

Topological Connectivity

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Critical Role of Molecular Symmetry for Charge Transport Properties: A Paradigm Learned from Quinoidal Bithieno[3,4-b]thiophenes

Chemistry of Materials ◽

10.1021/acs.chemmater.7b01551 ◽

2017 ◽

Vol 29 (11) ◽

pp. 4999-5008 ◽

Cited By ~ 15

Author(s):

Longbin Ren ◽

Dafei Yuan ◽

Eliot Gann ◽

Yuan Guo ◽

Lars Thomsen ◽

...

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Critical Role ◽

Molecular Symmetry

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The Role of the SLP in Autism Spectrum Disorder Screening and Assessment

Perspectives on Language Learning and Education ◽

10.1044/lle15.2.50 ◽

2008 ◽

Vol 15 (2) ◽

pp. 50-59 ◽

Cited By ~ 1

Author(s):

Amy Philofsky

Keyword(s):

Language Development ◽

Critical Role ◽

Children With Autism ◽

Autism Spectrum ◽

Children With Asd ◽

Prevalence Estimates ◽

Notable Increase ◽

Screening Assessment ◽

Critical Components

AbstractRecent prevalence estimates for autism have been alarming as a function of the notable increase. Speech-language pathologists play a critical role in screening, assessment and intervention for children with autism. This article reviews signs that may be indicative of autism at different stages of language development, and discusses the importance of several psychometric properties—sensitivity and specificity—in utilizing screening measures for children with autism. Critical components of assessment for children with autism are reviewed. This article concludes with examples of intervention targets for children with ASD at various levels of language development.

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