posted on 2020-03-05, 13:07authored byC. Redondo-Obispo, I. Suárez, S.J. Quesada, T. S. Ripolles, J. P. Martínez-Pastor, A. L. Álvarez, A. de Andrés, Carmen Coya
The
poor photostability under ambient conditions of hybrid halide
perovskites has hindered their recently explored promising nonlinear
optical properties. Here, we show how Bi3+ can partially
substitute Pb2+ homogeneously in the commonly studied MAPbI3, improving both environmental stability and photostability
under high laser irradiation. Bi content around 2 atom % produces
thin films where the nonlinear refractive (n2) and absorptive coefficients (β), which modify the
refractive index (Δn) of the material with
light fluence (I), increase up to factors of 4 and
3.5, respectively, compared to undoped MAPbI3. Higher doping
inhibits the nonlinear parameters; however, the samples show higher
fluence damage thresholds. Thus, these results provide a road map
on how MAPbI3 can be engineered for practical cost-effective
nonlinear applications by means of Bi doping, including optical limiting
devices and multiple-harmonic generation into optoelectronics devices.