A detailed study of the carrier absorption (CA) mechanism in multilayered silicon-nanocrystal (Si-nc) rib waveguides is reported. A pump (532 nm) and probe (1535 nm) technique is used to assess two loss mechanisms due to optical excitation of the system: one characterized by slow (seconds) dynamics related to heating and the other charaterized by fast (microsecond) dynamics associated to CA mechanisms within the Si-nc. CA losses increase with the pumping flux of up to 6 dB/cm for 3x10^20 photons/cm^2 s. by comparing the temporal dynamics of CA losses and time resolved photoluminescence, we suggest that both are determined by exciton generation and recombination.
Quantification of the carrier absorption losses in Si-nanocrystal rich rib waveguides at 1.54 micrometer
Daldosso, Nicola;Pucker, Georg;
2008
Abstract
A detailed study of the carrier absorption (CA) mechanism in multilayered silicon-nanocrystal (Si-nc) rib waveguides is reported. A pump (532 nm) and probe (1535 nm) technique is used to assess two loss mechanisms due to optical excitation of the system: one characterized by slow (seconds) dynamics related to heating and the other charaterized by fast (microsecond) dynamics associated to CA mechanisms within the Si-nc. CA losses increase with the pumping flux of up to 6 dB/cm for 3x10^20 photons/cm^2 s. by comparing the temporal dynamics of CA losses and time resolved photoluminescence, we suggest that both are determined by exciton generation and recombination.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
