1 research outputs found
Two-Photon Absorption and Two-Photon-Induced Gain in Perovskite Quantum Dots
Perovskite
quantum dots (PQDs) emerged as a promising class of
material for applications in lighting devices, including light emitting
diodes and lasers. In this work, we explore nonlinear absorption properties
of PQDs showing the spectral signatures and the size dependence of
their two-photon absorption (2PA) cross-section, which can reach values
higher than 10<sup>6</sup> GM. The large 2PA cross section allows
for low threshold two-photon induced amplified spontaneous emission
(ASE), which can be as low as 1.6 mJ/cm<sup>2</sup>. We also show
that the ASE properties are strongly dependent on the nanomaterial
size, and that the ASE threshold, in terms of the average number of
excitons, decreases for smaller PQDs. Investigating the PQDs biexciton
binding energy, we observe strong correlation between the increasing
on the biexciton binding energy and the decreasing on the ASE threshold,
suggesting that ASE in PQDs is a biexciton-assisted process