Halide perovskites exhibit unique slow hot-carrier cooling properties capable of unlocking disruptive perovskite photon–electron conversion technologies (e.g., high-efficiency hot-carrier photovoltaics, photo-catalysis, and photodetectors). Presently, the origins and mechanisms of this retardation remain highly contentious (e.g., large polarons, hot-phonon bottleneck, acoustical–optical phonon upconversion etc.). Here, we investigate the fluence-dependent hot-carrier dynamics in methylammonium lead triiodide using transient absorption spectroscopy, and correlate with theoretical modeling and first-principles calculations. At moderate carrier concentrations (around 1018 cm−3), carrier cooling is mediated by polar Fröhlich electron–phonon interactions through zone-center delayed longitudinal optical phonon emissions (i.e., with phonon lifetime τ LO around 0.6 ± 0.1 ps) induced by the hot-phonon bottleneck. The hot-phonon effect arises from the suppression of the Klemens relaxation pathway essential for longitudinal optical phonon decay. At high carrier concentrations (around 1019 cm−3), Auger heating further reduces the cooling rates. Our study unravels the intricate interplay between the hot-phonon bottleneck and Auger heating effects on carrier cooling, which will resolve the existing controversy.
%0 Journal Article
%1 fu2017carrier
%A Fu, Jianhui
%A Xu, Qiang
%A Han, Guifang
%A Wu, Bo
%A Huan, Cheng Hon Alfred
%A Leek, Meng Lee
%A Sum, Tze Chien
%D 2017
%J Nature Communications
%K hot_carrier perovskite
%N 1
%P 1300--
%R 10.1038/s41467-017-01360-3
%T Hot carrier cooling mechanisms in halide perovskites
%U https://doi.org/10.1038/s41467-017-01360-3
%V 8
%X Halide perovskites exhibit unique slow hot-carrier cooling properties capable of unlocking disruptive perovskite photon–electron conversion technologies (e.g., high-efficiency hot-carrier photovoltaics, photo-catalysis, and photodetectors). Presently, the origins and mechanisms of this retardation remain highly contentious (e.g., large polarons, hot-phonon bottleneck, acoustical–optical phonon upconversion etc.). Here, we investigate the fluence-dependent hot-carrier dynamics in methylammonium lead triiodide using transient absorption spectroscopy, and correlate with theoretical modeling and first-principles calculations. At moderate carrier concentrations (around 1018 cm−3), carrier cooling is mediated by polar Fröhlich electron–phonon interactions through zone-center delayed longitudinal optical phonon emissions (i.e., with phonon lifetime τ LO around 0.6 ± 0.1 ps) induced by the hot-phonon bottleneck. The hot-phonon effect arises from the suppression of the Klemens relaxation pathway essential for longitudinal optical phonon decay. At high carrier concentrations (around 1019 cm−3), Auger heating further reduces the cooling rates. Our study unravels the intricate interplay between the hot-phonon bottleneck and Auger heating effects on carrier cooling, which will resolve the existing controversy.
@article{fu2017carrier,
abstract = {Halide perovskites exhibit unique slow hot-carrier cooling properties capable of unlocking disruptive perovskite photon–electron conversion technologies (e.g., high-efficiency hot-carrier photovoltaics, photo-catalysis, and photodetectors). Presently, the origins and mechanisms of this retardation remain highly contentious (e.g., large polarons, hot-phonon bottleneck, acoustical–optical phonon upconversion etc.). Here, we investigate the fluence-dependent hot-carrier dynamics in methylammonium lead triiodide using transient absorption spectroscopy, and correlate with theoretical modeling and first-principles calculations. At moderate carrier concentrations (around 1018 cm−3), carrier cooling is mediated by polar Fröhlich electron–phonon interactions through zone-center delayed longitudinal optical phonon emissions (i.e., with phonon lifetime τ LO around 0.6 ± 0.1 ps) induced by the hot-phonon bottleneck. The hot-phonon effect arises from the suppression of the Klemens relaxation pathway essential for longitudinal optical phonon decay. At high carrier concentrations (around 1019 cm−3), Auger heating further reduces the cooling rates. Our study unravels the intricate interplay between the hot-phonon bottleneck and Auger heating effects on carrier cooling, which will resolve the existing controversy.},
added-at = {2018-01-17T16:21:08.000+0100},
author = {Fu, Jianhui and Xu, Qiang and Han, Guifang and Wu, Bo and Huan, Cheng Hon Alfred and Leek, Meng Lee and Sum, Tze Chien},
biburl = {https://www.bibsonomy.org/bibtex/249194667204a4ef7ab0ec84a3e27ca94/bretschneider_m},
doi = {10.1038/s41467-017-01360-3},
interhash = {efbcc4c943d9d1b762c10a8408e9646d},
intrahash = {49194667204a4ef7ab0ec84a3e27ca94},
issn = {20411723},
journal = {Nature Communications},
keywords = {hot_carrier perovskite},
number = 1,
pages = {1300--},
refid = {Fu2017},
timestamp = {2018-01-17T16:21:08.000+0100},
title = {Hot carrier cooling mechanisms in halide perovskites},
url = {https://doi.org/10.1038/s41467-017-01360-3},
volume = 8,
year = 2017
}