Dynamic Optical Properties of CH₃NH₃PbI₃ Single Crystals As Revealed by One- and Two-Photon Excited Photoluminescence Measurements.
The dynamic optical properties of perovskite CH3NH3PbI3 single crystals were studied by means of time-resolved photoluminescence (PL) spectroscopy at room temperature. The PL peak under one-photon excitation exhibits a red-shift with elapsing time, while two-photon PL is time-independent and appears at lower energy levels. The low-energy two-photon PL can be attributed to emissions from the localized states because of strong band-to-band absorption and photon re-absorption of the emitted light in the interior region. We revealed that the PL behaviors can be explained by the diffusion of photocarriers generated in the near-surface region to the interior region. The excitation fluence dependence of the one-photon PL dynamics is also discussed in terms of the electron-hole radiative recombination and carrier diffusion effects.
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Yasuhiro
Y
Yamada
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Takumi
T
Yamada
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Le Quang
le Q
Phuong
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Naoki
N
Maruyama
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Hidetaka
H
Nishimura
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Atsushi
A
Wakamiya
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Yasujiro
Y
Murata
Institute for Chemical Research, Kyoto University , Uji, Kyoto 611-0011, Japan.
Yoshihiko
Y
Kanemitsu