Journal
NANO LETTERS
Volume 15, Issue 3, Pages 1553-1558Publisher
AMER CHEMICAL SOC
DOI: 10.1021/nl5039314
Keywords
Spintronics; circular pump-probe; spin polarization; spin dynamics; Faraday rotation
Categories
Funding
- NTU [M4080514, M4081293]
- SPMS [M4080536]
- Ministry of Education AcRF [MOE2013-T2-1-081]
- Singapore NRF through Competitive Research Program [NRF-CRP4-2008-03]
- Singapore-Berkeley Research Initiative for Sustainable Energy (SinBeR-ISE) CREATE Programme
- National Natural Science Fund of China [11304186, 11247290]
- European Research Council [ARG 247404]
Ask authors/readers for more resources
Low-temperature solution-processed organic-inorganic halide perovskite CH3NH3PbI3 has demonstrated great potential for photovoltaics and light-emitting devices. Recent discoveries of long ambipolar carrier diffusion lengths and the prediction of the Rashba effect in CH3NH3PbI3, that possesses large spin-orbit coupling, also point to a novel semiconductor system with highly promising properties for spin-based applications. Through circular pump-probe measurements, we demonstrate that highly polarized electrons of total angular momentum (J) with an initial degree of polarization P-ini similar to 90% (i.e., -30% degree of electron spin polarization) can be photogenerated in perovskites. Time-resolved Faraday rotation measurements reveal photoinduced Faraday rotation as large as 10 degrees/mu m at 200 K (at wavelength lambda = 750 nm) from an ultrathin 70 nm film. These spin polarized carrier populations generated within the polycrystalline perovskite films, relax via intraband carrier spin-flip through the Elliot-Yafet mechanism. Through a simple two-level model, we elucidate the electron spin relaxation lifetime to be similar to 7 ps and that of the hole is similar to 1 ps. Our work highlights the potential of CH3NH3PbI3 as a new candidate for ultrafast spin switches in spintronics applications.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available