Ultralow-threshold multiphoton-pumped lasing from colloidal nanoplatelets in solution.

ABSTRACT: Although multiphoton-pumped lasing from a solution of chromophores is important in the emerging fields of nonlinear optofluidics and bio-photonics, conventionally used organic dyes are often rendered unsuitable because of relatively small multiphoton absorption cross-sections and low photostability. Here, we demonstrate highly photostable, ultralow-threshold multiphoton-pumped biexcitonic lasing from a solution of colloidal CdSe/CdS nanoplatelets within a cuvette-based Fabry-Pérot optical resonator. We find that colloidal nanoplatelets surprisingly exhibit an optimal lateral size that minimizes lasing threshold. These nanoplatelets possess very large gain cross-sections of 7.3 × 10(-14)?cm(2) and ultralow lasing thresholds of 1.2 and 4.3?mJ?cm(-2) under two-photon (?exc=800?nm) and three-photon (?exc=1.3??m) excitation, respectively. The highly polarized emission from the nanoplatelet laser shows no significant photodegradation over 10(7) laser shots. These findings constitute a more comprehensive understanding of the utility of colloidal semiconductor nanoparticles as the gain medium in high-performance frequency-upconversion liquid lasers.

SUBMITTER: Li M 

PROVIDER: S-EPMC4598837 | biostudies-other | 2015

REPOSITORIES: biostudies-other