期刊
NATURE COMMUNICATIONS
卷 6, 期 -, 页码 -出版社
NATURE PUBLISHING GROUP
DOI: 10.1038/ncomms9420
关键词
-
资金
- Engineering and Physical Sciences Research Council
- Winton Programme (Cambridge) for the Physics of Sustainability
- Cambridge Commonwealth Trust
- Rutherford Foundation of New Zealand
- German Research Foundation (DFG) [BR 4869_1-1]
- Rutherford Discovery Fellowship
- Marsden Fund
- Herchel Smith Research Fellowship
- EPSRC [EP/G060738/1, EP/M005143/1] Funding Source: UKRI
- Engineering and Physical Sciences Research Council [EP/M005143/1, EP/G060738/1] Funding Source: researchfish
Metal-halide perovskites are at the frontier of optoelectronic research due to solution processability and excellent semiconductor properties. Here we use transient absorption spectroscopy to study hot-carrier distributions in CH3NH3PbI3 and quantify key semiconductor parameters. Above bandgap, non-resonant excitation creates quasi-thermalized carrier distributions within 100 fs. During carrier cooling, a sub-bandgap transient absorption signal arises at similar to 1.6 eV, which is explained by the interplay of bandgap renormalization and hot-carrier distributions. At higher excitation densities, a 'phonon bottleneck' substantially slows carrier cooling. This effect indicates a low contribution from inelastic carrier-impurity or phonon-impurity scattering in these polycrystalline materials, which supports high charge-carrier mobilities. Photoinduced reflectivity changes distort the shape of transient absorption spectra and must be included to extract physical constants. Using a simple band-filling model that accounts for these changes, we determine a small effective mass of m(r) = 0.14 m(o), which agrees with band structure calculations and high photovoltaic performance.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据