Quantum dot spontaneous emission control in a ridge waveguide - Archive ouverte HAL
Journal Articles Applied Physics Letters Year : 2015

Quantum dot spontaneous emission control in a ridge waveguide

Abstract

We investigate the spontaneous emission (SE) of self-assembled InAs quantum dots (QDs) embedded in GaAs ridge waveguides that lay on a low index substrate. In thin enough waveguides, the coupling to the fundamental guided mode is vanishingly small. A pronounced anisotropy in the coupling to non-guided modes is then directly evidenced by normal-incidence photoluminescence polarization measurements. In this regime, a measurement of the QD decay rate reveals a SE inhibition by a factor up to 4. In larger wires, which ensure an optimal transverse confinement of the fundamental guided mode, the decay rate approaches the bulk value. Building on the good agreement with theoretical predictions, we infer from calculations the fraction β of SE coupled to the fundamental guided mode for some important QD excitonic complexes. For a charged exciton (isotropic in plane optical dipole), β reaches 0.61 at maximum for an on-axis QD. In the case of a purely transverse linear optical dipole, β increases up to 0.91. This optimal configuration is achievable through the selective excitation of one of the bright neutral excitons.
Fichier principal
Vignette du fichier
P159.pdf (1.17 Mo) Télécharger le fichier
Origin Publisher files allowed on an open archive
Loading...

Dates and versions

hal-01381358 , version 1 (14-10-2016)

Identifiers

Cite

Petr Stepanov, Adrien Delga, Xiaorun Zang, Joël Bleuse, Emmanuel Dupuy, et al.. Quantum dot spontaneous emission control in a ridge waveguide. Applied Physics Letters, 2015, 106, pp.41112 - 121108. ⟨10.1063/1.4906921⟩. ⟨hal-01381358⟩
215 View
445 Download

Altmetric

Share

More