49 research outputs found
Exciton-photon complexes and dynamics in the concurrent strong-weak coupling regime of singular site-controlled cavity quantum electrodynamics
We investigate the exciton complexes photoluminescence, dynamics and photon
statistics in the concurrent strong weak coupling regime in our unique site
controlled singular inverted pyramidal InGaAs/GaAs quantum dots photonic
crystal cavities platform. Different from a clear boundary between strong and
weak QD cavity coupling, we demonstrate the strong and weak coupling can
coexist dynamically, as a form of intermediate regime mediated by phonon
scattering. The detuning dependent microphotoluminescence spectrum reveals
concurrence of exciton cavity polariton mode avoided crossing, as a signature
of Rabi doublet of the strong coupled system, the blue shifting of coupled
exciton cavity mode energy near zero detuning ascribed to the formation of
collective states mediated by phonon assisted coupling, and their partial out
of synchronization linewidth narrowing linked to their mixed behavior. By
detailing the optical features of strongly confined exciton-photon complexes
and the quantum statistics of coupled cavity photons, we reveal the dynamics
and antibunching/bunching photon statistical signatures of the concurrent
strong weak intermediate coupled system at near zero-detuning. This study
suggests our device has potential for new and subtle cavity quantum
electrodynamical phenomena, cavity enhanced indistinguishable single photon
generation, and cluster state generation via the exciton-photon complexes for
quantum networks
On-chip single photon transfer with site-controlled quantum dots coupled to photonic crystal waveguides
Site-controlled quantum dots coupled to photonic crystal waveguides
We demonstrate selective optical coupling of multiple, site controlled semiconductor quantum dots (QDs) to photonic crystal waveguide structures. The impact of the exact position and emission spectrum of the QDs on the coupling efficiency is elucidated. The influence of optical disorder and end-reflections on photon transport in these systems are discussed
Epitaxie en phase vapeur a partir d'organometalliques de GaAs et de Ga_1_-_xAl_xAs pour applications photovoltaieques multispectrales
SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Large mode splitting and lasing in optimally coupled photonic-crystal microcavities
Coupling of L-type photonic-crystal (PhC) cavities in a geometry that follows inherent cavity field distribution is exploited for demonstrating large mode splitting of up to similar to 10-20 nm (similar to 15-30 meV) near 1 mu m wavelength. This is much larger than the disorder-induced cavity detuning for conventional PhC technology, which ensures reproducible coupling. Furthermore, a microlaser based on such optimally coupled PhC cavities and incorporating quantum wire gain medium is demonstrated, with potential applications in fast switching and modulation. (C)2011 Optical Society of Americ
Vertical cavity surface emitting laser
An electrically pumped VCSEL (10) and a method of its fabrication are presented. The VCSEL (10) comprises an active cavity material (14) sandwiched between top and bottom DBR stacks (12a, 12b), the top DBR (12b) having at least one n-semiconductor layer. The device defines an aperture region (25) between the structured surface (14b) of the active cavity material (14) and the n-semiconductor layer of the top DBR stack (12b). The structured surface (14b) is formed by a top surface of a mesa (22) that includes at least the upper n layer of a p/n tunnel junction and the surface of a p-type layer outside the mesa (22). The structured surface (14b) is fused to the surface of the n-semiconductor layer of the DBR stack (12b) due to the deformation of these surfaces, thereby creating an air gap (24) in the vicinity of the mesa (22) between the fused surfaces. The active region is defined by the current aperture (25) which includes the mesa (22) surrounded by the air gap (24), thereby allowing for restricting an electrical current flow to the active region, while the air gap (24) provides for the lateral variation of the index of refraction in the VCSEL (10)
Laser a cavite verticale et a emission par surface
A tunable Fabry-Perot vertical cavity photonic device and a method of its fabrication are presented. The device comprises top and bottom semiconductor DBR stacks and a tunable air-gap cavity therebetween. The air-gap cavity is formed within a recess in a spacer above the bottom DBR stack. The top DBR stack is carried by a supporting structure in a region thereof located above a central region of the recess, while a region of the supporting structure above the recess and outside the DBR stack presents a membrane deflectable by the application of a tuning voltage to the device contacts
Dense arrays of site-controlled quantum dots with tailored emission wavelength: Growth mechanisms and optical properties
2-mu m WAVELENGTH RANGE InGa(Al)As/InP-AlGaAs/GaAs WAFER FUSED VCSELs for SPECTROSCOPIC APPLICATIONS
We demonstrate 2-mu m wavelength, wafer-fused InGa(Al)As/InP-AlGaAs/GaAs vertical-cavity surface-emitting lasers (VCSELs) emitting single-mode power of 0.5 mW at room-temperature with a threshold current of 4mA and side-mode suppression ratio of over 30 dB. Emission wavelength can be continuously tuned with current by similar to 5 nm without mode hopping with a tuning rate of 0.31 nm/mA. These features demonstrate the long wavelength VCSELs potential for gas sensing and other optical spectroscopy applications