The evolution of ultrafast carrier dynamics <i>in-situ</i> perovskite optoelectronic devices

Although significant progresses have been made toward to optoelectronics application including solar cells, large color gamut LEDs, photodetectors, and X-ray detectors, the fundamental understanding of ultrafast carrier dynamics of organic-inorganic perovskite materials remains unclear. The ultrafast dynamics, which reveals some novel physical phenomena such as hot carrier cooling, phonon bottle-neck effect, and many-body problem was widely studied by ultrafast optical spectroscopies, which include pump-probe transient absorption (transmission, reflection, time-resolved THz, optical Kerr effect, and the most popular time-resolved photoluminescence(TRPL). However, it remains a challenge to study the perovskite optoelectronic devices in-situ in an ultrafast fashion.
In this talk, we use an ultrafast photocurrent spectroscopy with sub-25 picosecond time resolution to reveal the evolution of ultrafast carrier dynamics from sub-25 ps to microsecond in-situ perovskite solar cells and photoconductors. We address the basic questions of carrier photogeneration, recombination, transport, trapping, in addition to directly extracting carrier mobility, lifetime, and the property of trap states such as density, energy level, and capture cross-section.