Nonlinear carrier dynamics in silicon nano-waveguides

Aldaya I.; Gil-Molina A.; Pita J.L.; Gabrielli L.H.; Fragnito H.L.; Dainese P.

Nonlinear carrier dynamics in silicon nano-waveguides

Tipo

Artigo

Data de publicação

2017

Periódico

Optica

Citações (Scopus)

36

Autores

Aldaya I.
Gil-Molina A.
Pita J.L.
Gabrielli L.H.
Fragnito H.L.
Dainese P.

Resumo

© 2017 Optical Society of America.The understanding of free-carrier dynamics in silicon photonic nano-waveguides and micro-cavities is fundamental to several nonlinear optical phenomena. Through time-resolved pump and probe experiments, a complex and nonlinear carrier recombination dynamics is revealed. Our results show that the carrier lifetime varies as the recombination evolves, with faster decay rates at the initial stages (with lifetime of ∼800 ps) and much slower lifetimes at later stages (up to ∼300 ns). The large surface-to-volume ratio in nano-waveguides enables clear observation of the effect of carrier trapping, manifesting as a decay curve that is highly dependent on the initial carrier density. Further, we demonstrate faster recombination rates by operating at high carrier density. Our results, along with a theoretical framework based on trap-assisted recombination statistics applied to nano-waveguides, can impact the dynamics of several nonlinear nanophotonic devices in which free carriers play a critical role, and open further opportunities to enhance the performance of all-optical silicon-based devices.

Assuntos Scopus

Free-carrier dynamics , Nanophotonic devices , Non-linear optical , Nonlinear carrier dynamics , Pump and probe experiments , Silicon-based devices , Theoretical framework , Trap-assisted recombinations