Saturation and self-lensing in self-assembled quantum dots with constant-wave driving

Abstract

The nonlinear optical response of self-assembled quantum dots to cw driving is analyzed via numerical simulations of a spatially resolved rate equation model. The saturation is shown to follow a behavior in between the one for a dominantly, homogeneously, and inhomogeneously broadened medium. Self-lensing is suggested to probe the refractive-index nonlinearities and to open a complementary way of characterizing phase-amplitude coupling (alpha factor) in quantum-dots samples. For conservative assumptions on current samples the minimum focal length is predicted to be +/-1.7 mm for an input beam with 15 mu m radius at a detuning of 1.1 inhomogeneous linewidths from gain center

Saturation of absorption and gain in a quantum dot diode with continuous-wave driving

“…These tendencies are in qualitative agreement with the simulations presented in Ref. 9 and were linked to the saturation properties of a Voigt- profile in which neither inhomogeneous nor homogeneous broadening are strongly dominating. Via I sat =2P sat c eff / ͑w x w y ͒, where P sat are the saturation powers reported in Fig.…”

“…However, room temperature absorptive and refractive index nonlinearities of ensembles of QD without inversion might be useful for photonic devices displaying optical bistability, optical pattern formation, spatial solitons, or slow light. [8][9][10] Hence, we are investigating the saturation of InAs QD emitting close to the telecommunication O-band with cw driving.…”

“…Then, the small-signal coefficient in the absorptive case ͑g Ϸ −27/ cm, see Ref. 9 and references therein͒ is totally determined by the reflectivity R 1 of the front facet. Indeed, ln 0.18/ ͑0.15 cm͒Ϸ−11.4/ cm in rough agreement with the experiment assuming some additional linear losses.…”

High density InAlAs/GaAlAs quantum dots for non-linear optics in microcavities

“…20 In the pulsed regime, different characteristic times have to be considered (pulse duration or recombination lifetime). 21 In the cw regime, QDs are expected, in general, to have a lower saturation intensity than material of lower confinement dimensionality. In Ref.…”

Nonlinear Optics and Saturation Behavior of Quantum Dot Samples Under Continuous Wave Driving

“…However, absorptive and refractive index nonlinearities of ensembles of QD without inversion might be useful for photonic devices displaying optical bistability, optical pattern formation, spatial solitons or slow light [22,23,24,25,26]. In particular, many of the current authors have an interest in spatial cavity solitons (CS), i.e.…”